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 Style aipamenaCruz, 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 aipamenaCruz, 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.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.