Darkoh, M. B. (1989). Combating desertification in the Southern African region: An updated regional assessment. UNEP.
Chicago-viite (17. p.)Darkoh, Michael B.K. Combating Desertification in the Southern African Region: An Updated Regional Assessment. [S.l.]: UNEP, 1989.
MLA-viite (9. p.)Darkoh, Michael B.K. Combating Desertification in the Southern African Region: An Updated Regional Assessment. UNEP, 1989.
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