Dyfyniad APA

R. Hay, D. (1988). Planning now for Irrigation and Drainage in the 21st century. American society of Civil Engineers.

Dyfyniad Arddull Chicago

R. Hay, Delynn. Planning Now for Irrigation and Drainage in the 21st Century. New York: American society of Civil Engineers, 1988.

Dyfyniad MLA

R. Hay, Delynn. Planning Now for Irrigation and Drainage in the 21st Century. American society of Civil Engineers, 1988.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.