Gaya APA

Langer, W, L., Gleason, S, E. (1952). The Challenge to Isolation (1937-1940) . New York: Harper & Brothers Publishers - New York.

Gaya MLA

Langer, William, L.., Gleason, S., Everett. "The Challenge to Isolation (1937-1940)". New York: Harper & Brothers Publishers - New York, 1952. Koleksi Elektronik.