Costello, M. A. (1989). Levels of living and their geographic context: Northern Mindanao, 1960-1980. NEDA-PDPR Project.
Chicago-viite (17. p.)Costello, Michael A. Levels of Living and Their Geographic Context: Northern Mindanao, 1960-1980. [Pasig]: NEDA-PDPR Project, 1989.
MLA-viite (9. p.)Costello, Michael A. Levels of Living and Their Geographic Context: Northern Mindanao, 1960-1980. NEDA-PDPR Project, 1989.
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