GAS MARKETING AGREEMENT

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                                                                    Exhibit 10.5

                             GAS MARKETING AGREEMENT

     THIS GAS MARKETING AGREEMENT (the "Agreement"), made and entered into the
____ day of ____________, by and between Mewbourne Oil Company ("MOC"), ,
Mewbourne Energy Partners __-A, L.P. (the "Partnership") and Mewbourne
Development Corporation ("MD").

Recitals

     1.    MD and the Partnership are participants in a drilling program (the
          "Program") governed by that certain Drilling Program Agreement dated
          __________, 200_ by and among MOC, the Partnership and MD (the
          "Program Agreement").

     2.    Under the terms of the Program Agreement, MOC is the "Program Manager"
          and also serves a the "Operator" of the "Program's" properties under
          the terms of a joint operating agreement.

     3.    MOC operates hundreds of oil and gas wells in which non-affiliated
          parties own working interests.

     4.    MOC has developed expertise in the marketing of natural gas produced
          from the wells it operates.

     5.    In recognition of MOC's gas marketing expertise, non-affiliated
          parties have contracted with MOC for gas marketing services on
          substantially the same terms as provided for in this Agreement.

AGREEMENT

     NOW THEREFORE, in consideration of the premises and of the respective