Gaya APA

Lobeck, ., Heddy, S, (. (1939). Geomorfology An Introduction To The Study Of Landscapes . New York: McGraw-Hill Book Company.

Gaya MLA

Lobeck, ., Heddy, Suwasono, (Editor). "Geomorfology An Introduction To The Study Of Landscapes". New York: McGraw-Hill Book Company, 1939. Text.