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                                                                    EXHIBIT 3.1

                       CERTIFICATE OF LIMITED PARTNERSHIP
                                       OF
                      MEWBOURNE ENERGY PARTNERS 99-A, L.P.


         This Certificate of Limited Partnership of MEWBOURNE ENERGY PARTNERS
99-A, L.P. (the "Partnership") is being executed and filed by the undersigned
general partner to form a limited partnership under the Delaware Revised
Uniform Limited Partnership Act.

                                  ARTICLE ONE

         The name of the limited partnership formed hereby is MEWBOURNE ENERGY
PARTNERS 99-A, L.P.

                                  ARTICLE TWO

         The address of the registered office of the Partnership in the State
of Delaware is Corporation Trust Center, 1209 Orange Street, Wilmington, County
of New Castle, Delaware.

                                 ARTICLE THREE

         The name and address of the registered agent of the Partnership in the
State of Delaware is The Corporation Trust Company, Corporation Trust Center,
1209 Orange Street, Wilmington, County of New Castle, Delaware.

                                  ARTICLE FOUR

         The name and business address of the general partner of the
Partnership is:

               Name                                   Business Address
               ----                                   ----------------

  Mewbourne Development Corporation                   3901 S. Broadway
                                                     Tyler, Texas 75701

         IN WITNESS WHEREOF, the undersigned has executed this Certificate of
Limited Partnership by and through a duly authorized officer thereof on this
1st day of April, 1999.

                                       MEWBOURNE DEVELOPMENT
                                       CORPORATION, Managing Partner



                                       By: /s/ J. Roe Buckley
                                           -------------------------------------
                                           J. Roe Buckley
                                           Treasurer