Cruz, W. D. (1987). The environmental effects of soil erosion: Economic valuation issues for Philippine uplands. College of Economics and Management, University of the Philippines at Los Baños.
Chicago-referens (17:e uppl.)Cruz, Wilfrido D. The Environmental Effects of Soil Erosion: Economic Valuation Issues for Philippine Uplands. College, Laguna: College of Economics and Management, University of the Philippines at Los Baños, 1987.
MLA-referens (9:e uppl.)Cruz, Wilfrido D. The Environmental Effects of Soil Erosion: Economic Valuation Issues for Philippine Uplands. College of Economics and Management, University of the Philippines at Los Baños, 1987.
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