David, W. (1984). Environmental effects of watershed modifications. Philippine Institute for Development Studies.
Chicago-referens (17:e uppl.)David, Wilfrido. Environmental Effects of Watershed Modifications. Makati, Metro Manila: Philippine Institute for Development Studies, 1984.
MLA-referens (9:e uppl.)David, Wilfrido. Environmental Effects of Watershed Modifications. Philippine Institute for Development Studies, 1984.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.