COnyango & Tolba Mostafa. (1992). The World environment 1972-1992: Two decades of challenge. Chapman & Hall.
Chicago-čujuhus (17. p.)COnyango juo Tolba Mostafa. The World Environment 1972-1992: Two Decades of Challenge. London: Chapman & Hall, 1992.
MLA-čujuhus (9. p.)COnyango juo Tolba Mostafa. The World Environment 1972-1992: Two Decades of Challenge. Chapman & Hall, 1992.
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