(2012). IE Business Cases. XP Oil Corporation in the Orinoquia Region. Instituto de Empresa SL.
Chicago-viite (17. p.)IE Business Cases. XP Oil Corporation in the Orinoquia Region. [S.l.]: Instituto de Empresa SL, 2012.
MLA-viite (9. p.)IE Business Cases. XP Oil Corporation in the Orinoquia Region. Instituto de Empresa SL, 2012.
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