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                                                                    EXHIBIT 3a.

                          Articles of Incorporation
                                      Of
                          Altara International, Inc.

I THE UNDERSIGNED natural person of the age of 21 years or more, as acting
incorporator of a corporation under the Private Corporations provisions Section
78-010, et. seq., NEVADA REVISED STATUTES, (hereinafter referred to as the
"N.R.S."), adopt the following Articles of Incorporation for such corporation

                                  ARTICLE I
                                      
                                     NAME

The name of the Corporation is ALTARA INTERNATIONAL, INC.

                                  ARTICLE II
                                      
                               PRINCIPAL OFFICE

The initial principal office of the Corporation shall be located at 8 South
Forth Street, Las Vegas, Nevada, 89106, and/or such other
place as the directors shall designate.

                                 ARTICLE III
                                      
                                   DURATION

The period of duration of the Corporation is perpetual.

                                  ARTICLE IV
                                      
                             PURPOSES AND POWERS

The purposes for which the Corporation is organized are to engage in any
activity or business not in conflict with the laws of the State of Nevada or of
the United States of America, and without limiting the generality of the
foregoing, specifically, to have and to exercise all the powers now or hereafter
conferred by the laws of the State of Nevada upon corporations organized and any
and all acts amendatory thereof and supplemental thereto.

                                  ARTICLE V
                                      
                              AUTHORIZED SHARES

The aggregate number of shares which the Corporation shall have authority to
issue is 25,000,000 shares, having a par value of $0.001 per share. The
stock shall be designated as Class "A" voting common stock and shall have the
same rights and preferences. The common stock shall not be divided into classes
and may not be issued in series. Fully paid stock of this Corporation shall not
be liable for any further call or assessment. The total capitalization of the

Corporation shall be $25,000.


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                                  ARTICLE VI
                                      
                              PRE-EMPTIVE RIGHTS

No stockholder of the Corporation shall, because of his ownership of stock, have
a pre-emptive or other right to purchase, subscribe for or take part of any of
the notes, debentures, bonds or other securities convertible into or carrying
options for warrants to purchase stock of the Corporation issued, optioned or
sold by it after its incorporation, except as may be otherwise stated in these
Articles of Incorporation or by an amended certificate of said Articles duly
filed, may at any time be issued, auctioned for sale and sold or disposed of by
the Corporation pursuant to the resolution of its Board of Directors to such
person, persons or organizations and upon such terms as may to such Board of
Directors seem proper, without first offering such stock or securities or any
part thereof to existing stockholders, except as required in Article V of these
Articles of Incorporation.

                                 ARTICLE VII
                                      
                               VOTING OF SHARES

Each outstanding share of the class "A" common stock of the Corporation shall be
entitled to one vote on each matter submitted to a vote at a meeting of the
stockholders. Each shareholder shall be entitled to vote his or its shares in
person or by proxy, executed in writing by such shareholder or by its duly
authorized attorney in fact. At each election for directors, every shareholder
entitled to vote at such election shall have the right to vote in person or by
proxy, the number of shares owned by his or it for as many persons as there are
directors to be elected and for whose election he or it has the right to vote,
but the shareholder shall have no right, whatsoever, to accumulate his or its
votes with regard to such election.

                                 ARTICLE VIII
                                      
                                  DIRECTORS

The governing board of this Corporation shall be called directors, and the
number of directors may from time to time be specified by the By-laws of the
Corporation at not less than one, nor more than fifteen. When the By-laws do not
specify the number of directors, the number of directors shall be three (3), or
equal to the number of shareholders should there be less than three initial
shareholders. The name of the initial director, being also the incorporator and
sole shareholder, is:

Name                                Address
Leslie H. Shaw                      3760 So. Highland Dr., #300, Salt Lake City,

                                    UT 84106


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which director shall hold office until the first meeting of the shareholders 
of the Corporation and until his or her successors have been duly elected and 
qualified. Directors need not be residents of the State of Nevada or 
shareholders of the Corporation.

                                  ARTICLE IX
                                      
                                 INCORPORATOR

The name and address of the sole incorporator and sole initial shareholder of
this Corporation is:

Name                                Address
Leslie H. Shaw                      3760 So. Highland Dr., #300, Salt Lake City,
                                    UT 84106


Dated this 8th day of February 1990.


                                                 /s/Leslie H. Shaw
                                                    Incorporator


State of Utah                       )
                                    )ss:
County of Salt Lake                 )

Personally appeared before me this 8th day of February 1990, Leslie H. Shaw,
signer of the foregoing instrument who being by me first duly sworn, declared
that she is the person who signed the foregoing as incorporator and that the
statements contained therein are true.


                                               /s/NOTARIAL SIGNATURE
[  SEAL  ]                                     Notary Public residing in
                                                 Salt Lake


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                               Amendment To The
                          Articles of Incorporation
                                      of
                               Zygon Corporation
              (Name Changed Herein to Essential Resources, Inc.)

         WHEREAS, there was issued by the Secretary of State a Charter dated
March 14, 1990, constituting and creating ALTARA INTERNATIONAL, INC., a
corporation organized under the laws of this state with its principal place of
business in Las Vegas, Nevada, and changed its name to Zygon Corporation on July
27, 1995, and a capital stock of Twenty-Five Thousand Dollars ($25,000.00),
divided into Twenty-Five Million (25,000,000) shares of a par value of one mill
(1/10 cent) each, empowering it to engage in any activity or business not in
conflict with the laws of the State of Nevada or of the United States of
America.

         The undersigned, President and Secretary of Zygon Corporation hereby
certify that by resolutions duly adopted unanimously by the Board of Directors
of the Company pursuant to written action effective as of January 10, 1996, and
by resolutions duly adopted by a majority of the shareholders of all classes of
stock outstanding and entitled to vote thereon of the Company pursuant to
written action effective as of January 10, 1996, amending the Articles of
Incorporation as follows:

         That Article I, be amended and changed to read as follows:

Name:         The name of the Corporation is Essential Resources, Inc.

         WHEREFORE, they pray that the Articles of Incorporation of Zygon
Corporation be so amended.

DATED this 12th day of January, 1996.




                                                  /s/Jerry Peterson
                                                  Jerry Peterson, President



/s/David R. Yeaman
David R. Yeaman, Secretary



STATE OF UTAH                       )
                                    :ss
County of Salt Lake                 )



         On this 12th day of January, 1996, before me, a notary public,


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personally appeared Jerry Peterson and David R. Yeaman, known to me to be the
persons whose names are subscribed to the within document, and acknowledge that
they executed the same.


/s/NOTARIAL SIGNATURE
Notary Public

[ SEAL ]

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                               AMENDMENT TO THE
                                      
                          ARTICLES OF INCORPORATION
                                      
                                      OF
                                      
                          ALTARA INTERNATIONAL, INC.
                                      
                  (NAME CHANGED HEREIN TO ZYGON CORPORATION)

         WHEREAS, there was issued by the Secretary of State a Charter dated
March 14, 1990, constituting and creating ALTARA INTERNATIONAL, Inc., a
corporation organized under the laws of the state with its principal place of
business in Las Vegas, Nevada, and a capital stock of Twenty-Five Thousand
Dollars ($25,000.00), divided into Twenty-Five Million (25,000,000) shares of a
par value of one mill (1/10 cent) each, empowering it to engage in any activity
or business not in conflict with the laws of the State of Nevada or of the
United States of America.

         The undersigned, President and Secretary of ALTARA INTERNATIONAL, Inc.
hereby certify that the special meeting of shareholders was held on July 18,
1995. At the time of the meeting there were 1,400,00 shares outstanding and
entitled to vote, 1,360,400 shares present in person or by proxy and the
1,360,400 shares voted in favor of no shares voting against, amending the
Articles of Incorporation as follows:

         That Article I, be amended and changed to read as follows:

Name:             The name of the Corporation is ZYGON CORPORATION

         WHEREFORE, they [  ] that the Articles of Incorporation of
ALTARA INTERNATIONAL, INC. be so amended.



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DATED this 18th day of July, 1995.




                                                 /s/JERRY PETERSON
                                                 Jerry Peterson, President



/s/ David R. Yeaman
David R. Yeaman, Secretary




STATE OF UTAH                       )
                                    ):
County of Salt Lake                 )

         On this 18th day of July, 1995, before me, a notary public, personally
appeared Jerry Peterson and David R. Yeaman, known to me to be the persons whose
names are subscribed to the within document, and acknowledge that they executed
the same.



/s/NOTARIAL SIGNATURE
Notary Public                                        [  SEAL   ]