Population Resources, Environment and the Philippine Futures. (1980). Probing our futures: The Philippines, 2000 A.D. PREPF.
Chicago-viite (17. p.)Population Resources, Environment and the Philippine Futures. Probing Our Futures: The Philippines, 2000 A.D. Metro-Manila: PREPF, 1980.
MLA-viite (9. p.)Population Resources, Environment and the Philippine Futures. Probing Our Futures: The Philippines, 2000 A.D. PREPF, 1980.
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