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                                                                     EXHIBIT 4.5

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                            MEWBOURNE ENERGY PARTNERS

                                    -A, L.P.

                         A DELAWARE LIMITED PARTNERSHIP

CERTIFICATE NUMBER                           NUMBER OF GENERAL PARTNER INTERESTS

                               THIS CERTIFIES THAT

IS A GENERAL PARTNER OF MEWBOURNE ENERGY PARTNERS -A , L.P., A DELAWARE LIMITED
PARTNERSHIP (THE "PARTNERSHIP"), OWNING THE NUMBER OF GENERAL PARTNER INTERESTS
IN THE PARTNERSHIP ABOVE SPECIFIED, EACH GENERAL PARTNER INTEREST HAVING AN
INITIAL PURCHASE PRICE FROM THE PARTNERSHIP OF ONE THOUSAND DOLLARS ($1,000.00).
EACH GENERAL PARTNER INTEREST IS SUBJECT TO ALL OF THE TERMS AND CONDITIONS OF
THE AGREEMENT OF PARTNERSHIP OF THE PARTNERSHIP AND ENTITLED TO ALL THE RIGHTS
AND PRIVILEGES STATED THEREIN. THIS CERTIFICATE IS INTENDED SOLELY TO PROVIDE IN
CONCISE FORM CERTAIN INFORMATION ABOUT THE OWNERSHIP OF GENERAL PARTNER
INTERESTS IN THE PARTNERSHIP. ALL RIGHTS, OBLIGATIONS AND OTHER ATTRIBUTES
(INCLUDING THOSE RELATING TO ASSIGNMENT AND TRANSFER) PERTAINING TO THE GENERAL
PARTNER INTERESTS DESCRIBED IN THIS CERTIFICATE ARE SET FORTH IN AND GOVERNED BY
THE AGREEMENT OF PARTNERSHIP OF THE PARTNERSHIP, TO WHICH REFERENCE MUST BE MADE
FOR DESCRIPTION OF SUCH RIGHTS, OBLIGATIONS AND OTHER ATTRIBUTES. THIS
CERTIFICATE IS NOT VALID UNLESS EXECUTED BY AN AUTHORIZED OFFICER OF THE
MANAGING PARTNER OF THE PARTNERSHIP.

                                    MEWBOURNE ENERGY PARTNERS, -A, L.P.

                                       BY: MEWBOURNE DEVELOPMENT CORPORATION,
                                           MANAGING PARTNER

DATED: ____________________            BY: ___________________________________
                                           J. ROE BUCKLEY, TREASURER

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         This Certificate and the Agreement of Partnership of the Partnership
are your evidence of ownership of General Partner Interests, and both should be
retained. This Certificate should be submitted to the Partnership in the event
of any proposed change in ownership of your General Partner Interests.

         For transfer purposes, please return this Certificate to Mewbourne
Development Corporation, Investor Services Department, 3901 S. Broadway, Tyler,
Texas 75701, (903) 561-2900.

         For Value received, the undersigned hereby sells, assigns and transfers
_________________ of the Limited Partner Interests represented by this
Certificate unto:

                  _____________________________________________
                           (Print Name of Transferee)

                  _____________________________________________
                         (Street Address of Transferee)

                  _____________________________________________
                              (City) (State) (Zip)

and does hereby irrevocably constitute and appoint the Managing Partner attorney
to transfer the said Limited Partner Interests on the books of the Partnership
with full power of substitution.

Subject to the terms of Section 8.1 of the Agreement of Partnership of the
Partnership, the undersigned consents/does not consent to the above-named
transferee's becoming a substituted Limited Partner in the Partnership.

Date: __________________________

  ___________________________________________________________________________
  (Signature* of Limited Partner Interest Holder or Authorized Representative)

  ___________________________________________________________________________
              (Signature* of Joint Limited Partner Interest Holder)

  ___________________________________________________________________________
                (Printed Name of Limited Partner Interest Holder)

  ___________________________________________________________________________
             (Printed Name of Joint Limited Partner Interest Holder)

Signed in presence of: ___________________________________________
                                       (Witness)

* NOTE: Please sign your name exactly as it is shown on the Certificate. When
General Partner Interests are held by joint tenants, both should sign. When
signing as attorney, executor, administrator, trustee, or guardian, please give
full title as such. If a corporation, please sign in full corporate name by an
authorized corporate officer, and indicate corporate office held by person
signing. If a partnership, please sign in partnership name by authorized person.