<PAGE>   1
                                                                   EXHIBIT 10.18


THIS WARRANT AND THE SECURITIES RECEIVABLE UPON EXERCISE HEREOF HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"),
OR ANY STATE SECURITIES LAWS AND MAY NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE
TRANSFERRED OR DISPOSED OF UNLESS AND UNTIL SUCH SECURITIES ARE REGISTERED UNDER
THE SECURITIES ACT AND APPLICABLE STATE SECURITIES LAWS OR AN OPINION OF LEGAL
COUNSEL IS DELIVERED TO THE COMPANY STATING THAT AN EXEMPTION FROM SUCH
REGISTRATION IS AVAILABLE.

                                     WARRANT

                                                                 WARRANT NO. W-1

         THIS CERTIFIES THAT, for value received, DIPL. ING. OTON TISCH (the
"Holder") is entitled at any time during the Exercise Period (as such term and
other capitalized terms are defined in Article 1 hereof), subject to the terms
and conditions set forth herein, to purchase from CELL ROBOTICS INTERNATIONAL,
INC., a Colorado corporation (the "Company"), 135,000 shares of Common Stock
(subject to adjustment as provided herein) at the Warrant Price, all on the
terms and conditions and pursuant to the provisions hereinafter set forth. This
Warrant is issued in consideration for the Holder's obligations under the Loan
Agreement.

1. DEFINITIONS.

         As used in this Warrant, the following terms have the respective
meanings set forth below:

         "Applicable Law" shall mean all laws, rules and regulations applicable
to the Person, conduct, action or covenant in question, including, but not
limited to, all applicable common law and equitable principles, all provisions
of all applicable state and federal constitutions, statutes, rules, regulations
and orders of governmental body, and all orders, judgments and decrees of all
courts and arbitrators.

         "Commission" shall mean the Securities and Exchange Commission or any
other federal agency then administering the Securities Act and other federal
securities laws.

         "Common Stock" shall mean the common stock, par value $.004 per share,
of the Company and any capital stock into which such common stock shall have
been changed and any other stock resulting from any reclassification of such
stock which is not preferred as to dividends or assets over any other class of
stock which shall be in effect from time to time.

         "Designated Office" shall have the meaning set forth in Article 7.

         "Exercise Period" shall mean the period commencing on the date on which
the loan provided by Holder to the Company pursuant to the Loan Agreement is
funded and ending at 5:00 p.m., local time, at the Designated Office on January
31, 2004.

         "Exercise Price" shall mean $1.125, subject to adjustment as provided
in Article 3.

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         "Loan Agreement" shall mean that certain Loan Agreement, dated January
31, 2001, by and among the Company, the Holder and the other persons named
therein.

         "Notice of Exercise" shall mean the form of Notice of Exercise attached
hereto as Exhibit A.

         "Person" shall mean any natural person, corporation, unincorporated
organization, trust, joint-stock company, joint venture, association, company,
limited or general partnership, any government or any agency or political
subdivision of any government.

         "Restricted Common Stock" shall mean shares of Common Stock which are,
or which upon their issuance on the exercise of this Warrant would be, evidenced
by a certificate bearing the restrictive legend set forth in Section 4.4.

         "Securities Act" shall mean the Securities Act of 1933, as amended, or
any similar federal statute, and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

         "Transfer" shall mean any disposition of the Warrant Stock or of any
interest therein, which would constitute a sale thereof within the meaning of
the Securities Act.

         "Warrant" shall mean this Warrant and all warrants issued upon
transfer, division or combination of, or in substitution for, this Warrant.

         "Warrant Price" shall mean an amount equal to (a) the number of shares
of Common Stock being purchased upon exercise of this Warrant pursuant to
Section 2.2, multiplied by (b) the Exercise Price as of the date of such
exercise.

         "Warrant Stock" shall mean the shares of Common Stock issued, issuable
or both (as the context may require) to the Holder of this Warrant upon the
exercise thereof.

2. RIGHTS GRANTED EXERCISE OF WARRANT.

         2.1. Right of Exercise. Subject to Section 9.1, the Holder shall be
entitled to exercise this Warrant at any time and from time to time during the
Exercise Period. Notwithstanding the foregoing or anything else contained herein
to the contrary, the number of shares of Warrant Stock that shall vest and
become exercisable under this Warrant shall be equal to the product of (a)
135,000, multiplied by (b) the quotient of (i) the aggregate principal amount of
the loans made by Holder to the Company pursuant to the Loan Agreement, divided
by (ii) the amount set forth opposite the Holder's name on Exhibit A attached to
the Loan Agreement.

         2.2. Manner of Exercise. Subject to the terms and conditions of this
Warrant, the Holder shall have the right to exercise this Warrant during
Exercise Period, in whole or in part, by delivering to the Company at the
Designated Office (a) a Notice of Exercise, duly executed by the Holder,
specifying the number of shares of Common Stock to be purchased, (b) payment of
the Warrant Price by certified or official bank check, (c) this Warrant and (d)
in the event this


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<PAGE>   3

Warrant is being exercised by any Person other than the Holder pursuant to this
Section 2.2, shall be accompanied by proof acceptable to the Company of the
right of such Person or Persons to exercise this Warrant. Upon receipt thereof,
the Company shall, as promptly as practicable, execute (or cause to be executed)
and deliver (or cause to be delivered) to the Holder a certificate or
certificates representing the aggregate number of full shares of Common Stock
issuable upon such exercise. The certificate or certificates so delivered shall
be, to the extent possible, in such denomination or denominations as the Holder
shall request in the Notice of Exercise and shall be registered in the name of
the Holder or, subject to the terms of this Warrant, such other name as shall be
designated in the Notice of Exercise. This Warrant shall be deemed to have been
exercised and such certificate or certificates shall be deemed to have been
issued, and the Holder and/or any other Person so designated to be named therein
shall be deemed to have become a holder of record of such shares for all
purposes, as of the date the items specified in clauses (a) through (d) above
are received by the Company. If this Warrant shall have been exercised in part,
the Company shall, at the time of delivery of the certificate or certificates
representing the shares of Common Stock being issued, deliver to the Holder a
new warrant evidencing the rights of the Holder to purchase the unpurchased
shares of Common Stock called for by this Warrant, which new warrant shall in
all other respects be identical with this Warrant, or, at the request of the
Holder, appropriate notation may be made on this Warrant and the same returned
to the Holder. Notwithstanding any provision herein to the contrary, the Company
shall not be required to register shares in the name of any Person who acquires
this Warrant (or part hereof) or any Warrant Stock otherwise than in accordance
with this Warrant.

         2.3. Payment of Taxes. The issuance of a certificate or certificates
for shares of Common Stock upon exercise of this Warrant shall be made without
charge for any stamp or other similar tax in respect of such issuance. However,
if any such certificate is to be issued in a name other than that of the Holder,
the Person or Persons requesting the issuance thereof shall pay to the Company
the amount of any tax which may be payable in respect of any transfer involved
in such issuance or shall establish to the satisfaction of the Company that such
tax has been paid.

         2.4. Fractional Shares. The Company shall not be required to issue
fractions of shares of Common Stock upon exercise of this Warrant or to
distribute certificates which evidence fractional shares of Common Stock. If the
exercise of this Warrant would result in a fractional share of Common Stock or
the right to acquire a fractional share of Common Stock, such fractional share
shall be disregarded and the number of shares of Common Stock issuable upon the
exercise of this Warrant shall be rounded up or down to the nearest whole share.
The Holder expressly waives his right to receive any fractional shares upon
exercise of this Warrant.

         2.5. Compliance with Law and Regulations. This Warrant and the
obligation of the Company to sell and deliver the shares of Warrant Stock
hereunder shall be subject to all Applicable Laws and to such approvals by any
government or regulatory agency as may be required. Notwithstanding any other
provision of this Warrant, this Warrant may not be exercised if its exercise, or
the receipt of the shares of Warrant Stock pursuant thereto, would be contrary
to Applicable Law.


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<PAGE>   4

3. ADJUSTMENTS AND ANTI-DILUTION PROVISIONS.

         3.1. Adjustment for Change in Capital Stock. In the event of any change
in the Common Stock of the Company by reason of any combination, subdivision,
split, reclassification, stock dividend or any similar change affecting the
Common Stock, then in any such event the number and kind of shares of Common
Stock subject to this Warrant and the Exercise Price shall be adjusted, in such
manner as the Board of Directors deems equitable to prevent substantial dilution
or enlargement of the rights granted to the Holder. The adjustment shall become
effective immediately after the record date in the case of a dividend or
distribution and immediately after the effective date in the case of a
subdivision, combination or reclassification. Such adjustment shall be made
successively whenever any event listed above shall occur.

         3.2. Reorganization of Company. If at any time while this Warrant is
outstanding and unexpired there shall be (a) a reorganization of the Company,
(b) a merger or consolidation of the Company with or into another entity in
which the Company is not the surviving entity, or a reverse triangular merger in
which the Company is the surviving entity but the shares of the Company's
capital stock outstanding immediately prior to the merger are converted by
virtue of the merger into other property, whether in the form of securities,
cash or otherwise, or (c) a sale or transfer of the Company's properties and
assets as, or substantially as, an entirety to any other Person, then lawful and
adequate provision will be made whereby the Holder will thereafter have the
right to purchase and receive upon the basis and upon the terms and conditions
specified in this Warrant and in lieu of the shares of Common Stock of the
Company immediately theretofore purchasable and receivable upon the exercise of
this Warrant, the kind and amount of stock and other securities and assets
(including, without limitation, cash) receivable upon such merger, consolidation
or sale by a holder of the number of shares of Common Stock of the Company
deliverable upon the exercise of this Warrant immediately prior to such merger,
consolidation or sale. In any such case, appropriate provisions will be made
with respect to the rights and interests of the Holder to the end that the
provisions hereof (including, without limitation, provisions for adjustments of
the Exercise Price and of the number of shares of Common Stock purchasable upon
the exercise of this Warrant) will thereafter be applicable, as nearly as may
be, in relation to any shares of stock, securities or assets thereafter
deliverable upon the exercise hereof. The foregoing provisions of this Section
3.2 shall similarly apply to successive reorganizations, mergers, consolidations
and sales and to the stock or securities of any other corporation that are at
the time receivable upon the exercise of this Warrant. If this Section 3.2
applies to a transaction, Section 3.1 shall not apply to such transaction.

         3.3. Notice of Adjustment. Whenever the Exercise Price is adjusted, the
Company shall promptly mail to the Holder a notice setting forth the Exercise
Price after such adjustment and setting forth a brief statement of the facts
requiring such adjustment. Such certificate prepared in good faith shall be
conclusive evidence of the correctness of such adjustment absent manifest error.

         3.4. Company Determination Final. Any determination that the Company or
the Board of Directors must make pursuant to this Warrant is conclusive absent
manifest error.


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<PAGE>   5

         3.5. When No Adjustment Required. No adjustment need be made for any
transaction referred to in Section 3.2 if the Holder is entitled to participate
in the transaction on a basis and with notice that the Board of Directors
determines to be fair and appropriate in light of the basis and notice on which
holders of Common Stock participate in the transaction. No adjustment need be
made for a change in the par value or no par value of the Common Stock.

4. RESTRICTIONS ON TRANSFER AND COMPLIANCE WITH SECURITIES ACT AND REGISTRATION.

         4.1 Agreement to Be Bound. The Holder, by acceptance of this Warrant,
agrees to be bound by the provisions of this Article 4. The Holder further
agrees that all shares of Warrant Stock will be disposed of only in accordance
with the Securities Act and the rules and regulations of the Commission
promulgated thereunder.

         4.2. Non-Transferability. This Warrant and the rights hereunder shall
not be transferable in whole or in part without the prior written consent of the
Company.

         4.3. Compliance with the Securities Act. This Warrant and the Warrant
Stock have not been registered under the Securities Act or any applicable state
securities law. The Holder hereof, by acceptance hereof, agrees that this
Warrant and all shares purchased upon exercise hereof will be disposed of only
in accordance with the Securities Act and the rules and regulations of the
Commission promulgated thereunder or of any applicable state securities law. The
Holder represents and warrants that (a) he, she or it is an "accredited
investor," as that term is defined in Rule 501(a) of Regulation D under the
Securities Act, and is acquiring the Common Stock for his, her or its own
account, for investment and not with a view to any "distribution" within the
meaning of the Securities Act; (b) he, she or it has been furnished with all
information which he, she or it deems necessary to evaluate the merits and risks
of this Warrant and the purchase of the Common Stock upon exercise thereof; (c)
he, she or it has had the opportunity to ask questions concerning the Common
Stock and the Company and all questions posed have been answered to his, her or
its satisfaction; (d) he, she or it has been given the opportunity to obtain any
additional information he, she or it deems necessary to verify the accuracy of
any information obtained concerning the Common Stock and the Company; and (e)
he, she or it has such knowledge and experience in financial and business
matters that he, she or it is able to evaluate the merits and risks of
purchasing the Common Stock and to make an informed investment decision relating
thereto.

         4.4. Restrictive Legends. Except as otherwise provided in this Article
4, each certificate for Warrant Stock initially issued upon the exercise of this
Warrant, and each certificate for Warrant Stock issued to any subsequent
transferee of any such certificate, shall be stamped or otherwise imprinted with
a legend in substantially the following form:

         "THE SHARES REPRESENTED BY THIS INSTRUMENT HAVE NOT BEEN REGISTERED
         UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR
         ANY STATE SECURITIES LAWS AND MAY NOT BE OFFERED, SOLD, PLEDGED OR
         OTHERWISE TRANSFERRED OR DISPOSED OF UNLESS AND UNTIL SUCH SECURITIES
         ARE REGISTERED UNDER THE SECURITIES ACT AND APPLICABLE STATE SECURITIES
         LAWS OR AN OPINION OF LEGAL


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<PAGE>   6

         COUNSEL IS DELIVERED TO THE COMPANY STATING THAT AN EXEMPTION FROM
         SUCH REGISTRATION IS AVAILABLE."

         4.5. Transfers. No shares of Restricted Common Stock issued upon the
exercise hereof shall be Transferred other than pursuant to an effective
registration statement under the Securities Act or, if required by the Company,
an opinion of counsel is delivered to the Company stating an exemption from the
registration provisions thereof. Each certificate, if any, evidencing such
shares of Restricted Common Stock issued upon any such Transfer, other than in a
public offering pursuant to an effective registration statement, shall bear the
restrictive legend set forth in Section 4.4, unless (a) such Transfer is in
accordance with the provisions of Rule 144 under the Securities Act (or any
other rule or provision permitting sale without registration under the
Securities Act), (b) such Restricted Common Stock shall have been effectively
registered under the Securities Act and disposed of pursuant thereto or (c) in
the opinion of counsel delivered at the request of the Holder, which opinion
shall be reasonably acceptable to the Company, such legend is not required for
the purposes of compliance with the Securities Act. The holder of the Restricted
Common Stock shall not be entitled to Transfer such Restricted Common Stock
except in accordance with this Section 4.5.

5. RESERVATION AND AUTHORIZATION OF COMMON STOCK.

         From and after the date of this Warrant, the Company shall at all times
reserve and keep available for issuance upon the exercise of this Warrant such
number of its authorized but unissued shares of Common Stock as will be
sufficient to permit the exercise in full of this Warrant. All shares of Common
Stock issuable pursuant to the terms hereof, when issued upon exercise of this
Warrant with payment therefor in accordance with the terms hereof, shall be duly
and validly issued and fully paid and nonassessable.

6. THEFT, LOSS, DESTRUCTION.

         Upon receipt by the Company from the Holder of evidence reasonably
satisfactory to it of the ownership of and the loss, theft, destruction or
mutilation of this Warrant and an indemnity reasonably satisfactory to it and,
in case of mutilation, upon surrender and cancellation hereof, the Company will
execute and deliver in lieu hereof a new Warrant of like tenor to the Holder;
provided, however, in the case of mutilation, no indemnity shall be required if
this Warrant in identifiable form is surrendered to the Company for
cancellation.

7. OFFICE OF THE COMPANY.

         As long as this Warrant remains outstanding, the Company shall maintain
an office or agency, which may be the principal executive offices of the Company
or the offices of the transfer agent of the Company (the "Designated Office"),
where this Warrant may be presented for exercise, registration of transfer,
division or combination as provided in this Warrant. Such Designated Office
shall initially be the principal office of the Company at 2715 Broadbent Parkway
N.E., Albuquerque, New Mexico 87107; thereafter, such office shall be the office
of the Company or of an agency designated by the Company in a notice delivered
to the Holder.


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<PAGE>   7

8. NO SHAREHOLDER RIGHTS.

         Prior to the exercise of this Warrant, the Holder of this Warrant shall
not be entitled to any rights of a shareholder of the Company, including,
without limitation, the rights to vote, to receive dividends or other
distributions, and shall not be entitled to receive any notice of any
proceedings of the Company except as provided herein.

9. MISCELLANEOUS.

         9.1. Termination of Warrant. Except those rights which by their terms
specifically extend beyond the end of the Exercise Period, this Warrant and all
rights granted herein, to the extent those rights have not lapsed or been
exercised, will terminate and become null and void at the end of the Exercise
Period or as otherwise specifically provided herein.

         9.2. Notices. All notices, requests, demands, claims and other
communications under this Warrant shall be in writing. Any notice, request,
demand, claim or other communication hereunder shall be deemed duly given if
(and then two business days after) it is sent by (a) confirmed facsimile; (b)
overnight delivery; or (c) registered or certified mail, return receipt
requested, postage prepaid, and addressed to the intended recipient as set forth
below:

        If to the Company:                Cell Robotics International, Inc.
                                          2715 Broadbent Parkway N.E.
                                          Albuquerque, New Mexico 87107
                                          Attn: Ronald K. Lohrding, Ph.D.
                                          Telephone:  (505) 343-1131
                                          Facsimile:  (505) 344-8112

        With a copy to, which copy        Baker & McKenzie
        shall not constitute notice:      2001 Ross Avenue, Suite 2300
                                          Dallas, Texas 75201
                                          Attn:  W. Crews Lott
                                          Telephone:  (214) 978-3000
                                          Facsimile:  (214) 978-3099

        If to the Holder:                 Dipl. Ing. Oton Tisch
                                          Apartado 76949
                                          Caracas 1070 Venezuela
                                          Telephone:  011-582-235-4175
                                          Facsimile:  011-582-239-7828

The Holder or the Company may send any notice, request, demand, claim or other
communication hereunder to the intended recipient at the address set forth above
using any other means (including personal delivery, expedited courier, messenger
service, telecopy, telex, ordinary mail or electronic mail), but no such notice,
request, demand, claim or other communication shall be deemed to have been duly
given unless and until it actually is received by the intended recipient. The
Holder or the Company may change the address to which notices,


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<PAGE>   8

requests, demands, claims and other communications hereunder are to be delivered
by giving the other party notice in the manner provided in this Warrant.

         9.3. Succession and Assignment. This Warrant shall be binding upon and
inure to the benefit of the Holder and the Company and their respective
successors and permitted assigns. Neither the Holder or the Company may assign
either this Warrant or any of its rights, interests or obligations hereunder
without the prior written approval of the other party.

         9.4. Severability. Any term or provision of this Warrant that is
invalid or unenforceable in any situation in any jurisdiction shall not affect
the validity or enforceability of the remaining terms and provisions hereof or
the validity or enforceability of the offending term or provision in any other
situation or in any other jurisdiction.

         9.5. Headings. The headings used in this Warrant are for the
convenience of reference only and shall not, for any purpose, be deemed a part
of this Warrant.

         9.6. Governing Law. THIS WARRANT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE DOMESTIC LAWS OF THE STATE OF NEW MEXICO WITHOUT GIVING
EFFECT TO ANY CHOICE OR CONFLICT OF LAW PROVISION OR RULE (WHETHER OF THE STATE
OF NEW MEXICO OR ANY OTHER JURISDICTION) THAT WOULD CAUSE THE APPLICATION OF THE
LAWS OF ANY JURISDICTION OTHER THAN THE STATE OF NEW MEXICO. Any legal action or
proceeding with respect to this Warrant shall be brought in any New Mexico state
or federal court sitting in Bernalillo County, New Mexico, and, by execution and
delivery of this Warrant, the Holder and the Company hereby accept for
themselves and in respect of their property, generally and unconditionally, the
jurisdiction of the aforesaid courts. The Holder and the Company hereby
irrevocably waive any objection, including, without limitation, any objection to
the laying of venue or based on the grounds of forum non conveniens, which they
may now or hereafter have to the bringing of any such action or proceeding in
such respective jurisdictions.

         IN WITNESS WHEREOF, the Company has caused this Warrant to be duly
executed by its President and CEO on the 31st day of January 2001.

                                CELL ROBOTICS INTERNATIONAL, INC.


                                By:
                                    --------------------------------------------
                                    Ronald K. Lohrding, Ph.D.
                                    President and CEO

Accepted and Agreed to by:


-----------------------------
Dipl. Ing. Oton Tisch


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<PAGE>   9

                                    EXHIBIT A

                             NOTICE OF EXERCISE FORM

(To be executed only upon partial or full exercise of the within Warrant)

         The undersigned registered Holder of the within Warrant irrevocably
exercises the within Warrant for and purchases _______ shares of Common Stock,
par value $0.004 per share ("Common Stock"), of CELL ROBOTICS INTERNATIONAL,
INC. (the "Company") and herewith makes payment therefor in the amount of
$___________, all at the price and on the terms and conditions specified in the
within Warrant and requests that a certificate (or ___________ certificates in
denominations of _________ shares) for the shares of Common Stock of the Company
hereby purchased be issued in the name of and delivered to (choose one) (a) the
undersigned or (b) ________, whose address is ___________, and, if such shares
of Common Stock shall not include all the shares of Common Stock issuable as
provided in the within Warrant, that a new Warrant of like tenor for the number
of shares of Common Stock of the Company not being purchased hereunder be issued
in the name of and delivered to (choose one) (a) the undersigned or (b)
_________, whose address is _________.

         The undersigned is aware that the Common Stock has not been registered
under the Securities Act of 1933, as amended (the "Securities Act"), or any
state securities laws. The undersigned understands that the reliance by the
Company on exemptions under the Securities Act is predicated in part upon the
truth and accuracy of the statements of the undersigned.

         The undersigned represents and warrants that (a) he, she or it is an
"accredited investor," as that term is defined in Rule 501(a) of Regulation D
under the Securities Act and is acquiring the Common Stock for his or her own
account, for investment and not with a view to any "distribution" within the
meaning of the Securities Act; (b) the undersigned has no present intention of
making any transfer of the Common Stock; (c) he, she or it has been furnished
with all information which he, she or it deems necessary to evaluate the merits
and risks of the purchase of the Common Stock; (d) he or she has had the
opportunity to ask questions concerning the Common Stock and the Company and all
questions posed have been answered to his, her or its satisfaction; (e) he, she
or it has been given the opportunity to obtain any additional information he,
she or it deems necessary to verify the accuracy of any information obtained
concerning the Common Stock and the Company; and (f) he, she or it has such
knowledge and experience in financial and business matters that he, she or it is
able to evaluate the merits and risks of purchasing the Common Stock and to make
an informed investment decision relating thereto.

         The undersigned understands that because the Common Stock has not been
registered under the Securities Act, he, she or it must continue to bear the
economic risk of the investment for an indefinite time and the Common Stock
cannot be sold unless the Common Stock is subsequently registered under
applicable federal and state securities laws or an exemption from such
registration is available.

         The undersigned agrees that he, she or it will in no event sell or
distribute or otherwise dispose of all or any part of the Common Stock unless
(a) there is an effective registration statement under the Securities Act and
applicable state securities laws covering any such transaction involving the
Common Stock, as applicable, or (b) such Common stock is sold in a



<PAGE>   10

transaction exempt from such registration. The undersigned agrees that, if
requested by the Company, and at the expense of the undersigned, he or she shall
deliver an opinion of counsel, which opinion shall be reasonably satisfactory to
the Company that such registration or qualification is not required.

         The undersigned consents to the placing of a legend on its certificate
for the Common Stock stating that the Common Stock has not been registered and
setting forth the restriction on transfer contemplated hereby and to the placing
of a stop transfer order on the books of the Company and with any transfer
agents against the shares until the Common Stock may be legally resold or
distributed without restriction.


Signature Guaranteed:        By:
                                 -----------------------------------------------
                             Name:
                                   ---------------------------------------------
                             Title:
                                    --------------------------------------------
                             Date:
                                   ---------------------------------------------

NOTICE: THE SIGNATURE TO THIS NOTICE OF EXERCISE MUST CORRESPOND WITH THE NAME
AS WRITTEN UPON THE FACE OF THE WITHIN WARRANT IN EVERY PARTICULAR, WITHOUT
ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER. THE SIGNATURE ON THIS NOTICE
OF EXERCISE MUST BE GUARANTEED BY A COMMERCIAL BANK OR TRUST COMPANY IN THE
UNITED STATES OR A MEMBER FIRM OF THE NEW YORK STOCK EXCHANGE.


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