Document:

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                                                                   Exhibit 10.21

                SUPPLEMENTAL LIMITED LIABILITY COMPANY AGREEMENT

                  This SUPPLEMENTAL LIMITED LIABILITY COMPANY AGREEMENT, dated
as of March     , 2000 (the "Agreement"), is entered into by and between WBT
Holdings LLC, a Delaware limited liability company (the "Company"), and the
individual listed on the signature page hereto (the "Individual").

                  WHEREAS, the Company desires to sell Units to
an additional member of the Company's management;

                  WHEREAS, the Individual desires to subscribe for and purchase,
and the Company desires to sell to the Individual the number of Units (the
"Units") subscribed for by the Individual pursuant to a Subscription Agreement,
dated as of the date hereof (the "Subscription Agreement"), between the Company
and the Individual; and

                  WHEREAS, the Company and the Individual desire to enter into
this Agreement in order to set forth their understanding with respect to certain
voting arrangements, transfer rights and other matters relating to the
Individual's ownership of Units and to acknowledge that any Units acquired by
the Individual pursuant to the Subscription Agreement are subject to, and
governed by, the Limited Liability Company Agreement (as defined below).

                  NOW, THEREFORE, in consideration of the mutual promises
contained in this Agreement and other good and valuable consideration the
receipt and sufficiency of which is hereby acknowledged, the parties to this
Agreement agree as follows:

                                    ARTICLE I

              INCORPORATION OF LIMITED LIABILITY COMPANY AGREEMENT

                  SECTION 1.1 Documentation With Respect to the Shares. The
Individual hereby acknowledges that the Units are subject to various agreements,
including with out limitation, the Limited Liability Company Agreement, dated as
of February 10, 2000 (as the same may be amended from time to time, the "Limited
Liability Company Agree-

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ment"), by and among the Company and the Members of the Company as set forth
therein. Terms not defined herein shall have the meanings set forth in the
Limited Liability Company Agreement.

                  SECTION 1.2 Access to Information. The Individual (i) has
reviewed the Limited Liability Company Agreement and the other materials
furnished to him in connection with the transactions contemplated hereby and
contemplated by the Subscription Agreement and (ii) has been granted the
opportunity to ask questions of, and has received answers from, representatives
of the Company and its affiliates concerning the terms and conditions of the
purchase of the Units and has been granted the opportunity to obtain any
additional information that he or she deems necessary to verify the accuracy of
the information contained in the Limited Liability Company Agreement and the
Subscription Agreement and such other materials.

                  SECTION 1.3 General. Upon the execution of this Agreement, the
Individual shall be deemed, in accordance with Article XIV of the Limited
Liability Company Agreement, to have the same rights and obligations as a Member
(as defined therein) for purposes of the Limited Liability Company Agreement.
The Individual hereby agrees to be bound by, and agrees that any Units acquired
pursuant to the Subscription Agreement are subject to, and governed by, the
terms and conditions of the Limited Liability Company Agreement. The Individual,
in accordance with Article XIV of the Limited Liability Company Agreement, is
hereby deemed to be a Management Member (as defined therein) for all purposes of
the Limited Liability Company Agreement. Pursuant to Section 14.3 of the
Limited Liability Company Agreement, this Agreement is effective as of the date
hereof.

                  SECTION 1.4 Conflict. In the event of a conflict between the
terms hereof and the Limited Liability Company Agreement, the terms of the
Limited Liability Company Agreement shall control.

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                                   ARTICLE II

                                  Miscellaneous

                  SECTION 2.1 After-Acquired Units. All of the provisions of
this Agreement shall apply to all of the securities of the Company now owned or
which may be issued or Transferred (as defined in the Limited Liability Company
Agreement) hereafter to the Individual in consequence of any additional
issuance, purchase (including, without limitation, pursuant to options to
purchase capital stock of the Company), exchange, conversion, or
reclassification of securities, corporate reorganization, or any other form of
recapitalization, consolidation, merger, unit split or unit dividend, or which
are acquired by the Individual in any other manner (all of which shall be
deemed to be "Units" hereunder).

                  SECTION 2.2 Specific Performance. The parties hereto
acknowledge that irreparable damage would result if this Agreement is not
specifically enforced and that, therefore, the rights and obligations of the
parties under this Agreement may be enforced by a decree of specific performance
issued by a court of competent jurisdiction, and appropriate injunctive relief
may be applied for and granted in connection therewith. Such remedies shall,
however, be cumulative and not exclusive and shall be in addition to any other
remedies which any party may have under this Agreement or otherwise.

                  SECTION 2.3 Terms of Agreement. This Agreement shall become
effective on the date hereof and shall continue in full force and effect until
the date on which the Limited Liability Company Agreement terminates.

                  SECTION 2.4 Successors and Assigns. All the terms and
provisions of this Agreement shall inure to the benefit of and be binding upon
the parties hereto and their respective successors and assigns; provided, how
ever, no party hereto may assign this Agreement or its rights or obligations
hereunder without the prior written consent of the other party hereto.

                  SECTION 2.5 Entire Agreement. This Agreement, the Limited
Liability Company Agreement and the Subscription Agreement constitute the
complete understanding and agreement among the parties hereto with respect to
the

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subject matter hereof and this Agreement can be amended, supplemented or
changed, and any provision hereof can be waived, only by written instrument
making specific reference to this Agreement signed by the party against whom
enforcement of any such amendment, supplement, modification or waiver is
sought.

                  SECTION 2.6 Approvals and Consents. The Individual hereby
agrees, for himself or herself, his or her heirs and legal representatives(s),
to prepare, execute and deliver or cause to be prepared, executed and delivered
such further instruments and documents, and to take such other actions as may be
reasonably required to more effectively carry out the intent and purposes of
this Agreement and the Limited Liability Company Agreement and the transactions
contemplated hereby and thereby.

                  SECTION 2.7 Notices. All notices, requests, demands and other
communications which are required or may be given hereunder shall be in writing
and shall be deemed to have been duly given to a party if delivered personally
or mailed by certified or registered mail, return receipt requested, postage
prepaid, or if given by telex or other telegraphic means, to such party at his
or its address set forth in Schedule A hereto. Any such notice shall for all
purposes of this Agreement be deemed to have been given, and received by the
addressee, on the date of such personal delivery or telex or telegraphic notice
or five (5) days after any such mailing thereof.

                  SECTION 2.8 Governing Law. This Agreement shall be governed by
and construed in accordance with the laws of the State of Delaware.

                  SECTION 2.9 Severability. If any provision of this Agreement
or the application of any such provision to any person or circumstances shall
be held invalid by a court of competent jurisdiction, the remainder of this
Agreement, including the remainder of the provision held invalid, or the
application of such provision to persons or circumstances other than those as to
which it is held invalid, shall not be affected thereby.

                  SECTION 2.10  Counterparts.  This Agreement may be executed in
one or more counterparts, each of which

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shall be deemed to be an original, but all of which together shall constitute
one and the same instrument.

                  SECTION 2.11 Headings. All section headings herein are for
convenience of reference and are not part of this Agreement, and no construction
or interference shall be derived therefrom.

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                  IN WITNESS WHEREOF, the parties hereto have hereunto set their
hands as of the date first set forth above.

                                                     ___________________________
                                                     Name: Lance D'Amico

                                                     WBT HOLDINGS LLC

                                                     By:________________________
                                                        Name:  Robert Fogelson
                                                               Title:

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                                                                      Schedule A

Individual:

Lance D'Amico

Company:

WBT HOLDINGS LLC

Units Purchased:           5,000

Capital Account:

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                                                                   EXHIBIT 10.22

                              ELEMENT K PRESS LLC
                                 ELEMENT K LLC
                            500 CANAL VIEW BOULEVARD
                           ROCHESTER, NEW YORK  14623

May 5, 2000

Dear Sir or Madam:

This letter agreement sets forth the general terms of our agreement relating to
a termination of your employment with Element K Press LLC (together with its
successors, " Element K Press") and Element K LLC (together with its successors,
"Element K"; each of Element K Press and Element K, a "Company" and
collectively, the "Companies"). The terms set forth in this letter agreement are
in addition to those terms contained in Section 5.2 of the Limited Liability
Company Agreement of each of Element K Press and Element K.

Terms of Separation

In the event your employment is terminated for Cause or by you other than for
Good Reason, your salary will cease to be payable. In the event your employment
is terminated other than for Cause or by you for Good Reason, or in the event of
your death or disability, you will receive a lump sum amount equal to your full
base salary for one year, payable in 30 days of your termination.

Cause/Good Reason

For purposes hereof, "Cause" shall mean a finding in good faith by the board of
directors of Element K Holdings LLC or Element K Press Holdings LLC that you

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Mr Howard Cohen
May 5, 2000
Page 2

have (a) materially failed, neglected or refused to perform your duties
(including as a result of alcohol or drug abuse), (b) committed any willful,
intentional or grossly negligent act having the effect of materially injuring
the interests, business, prospects or reputation of either of the Companies or
any of their affiliates or divisions, (c) engaged in any willful misconduct in
respect of you duties or obligations, (d) violated or failed to comply in any
material respect with the Companies' published rules, regulations or policies,
as in effect from time to time, (e) committed a felony or misdemeanor involving
moral turpitude, fraud, theft or dishonesty (including entry of a nolo
contendere plea), (f) misappropriated or embezzled any property of either the
Company or its affiliates (whether or not a misdemeanor or a felony), and (g)
breached this agreement or any option agreement to which you are a party;
provided, in the case of clause (a), (d) or (g) above, that you shall have been
given notice of such Cause and failed within 20 days of such notice to have
substantially rectified or corrected the same.

For purposes hereof, "Good Reason" shall mean, in the absence of your consent,
(a) any material reduction in duties or responsibilities or any adverse change
in titles, (b) any requirement that you be based in an office more than 30 miles
from the Companies' current headquarters, (c) any reduction in base salary,
target bonus or vacation time, as the same may be increased from time to time,
or (d) any breach of this agreement by the Companies which shall not have been
substantially rectified or corrected within 20 days of notice hereof.

Enforcement

In the event of litigation between you on the one hand and either the Company or
any Company affiliate on the other hand regarding the terms of this agreement,
the prevailing party shall be entitled to receive an amount equal to its
reasonable out-of-pocket legal fees and expenses in respect thereof.

Amendment

This agreement may only be amended by written agreement of the parties hereto.

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Mr. Howard Cohen
May 5, 2000
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                                                     ELEMENT K PRESS LLC

<TABLE>
<S>                                                <C>
                                                     By:
                                                         ------------------------------
                                                     Name: Bruce Barnes
                                                     Title: Chief Executive Officer

                                                     ELEMENT K LLC

                                                     By:
                                                        -------------------------------
                                                     Name: Bruce Barnes
                                                     Title: Chief Executive Officer
</TABLE>

Accepted and Agreed to by:

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