Cita APA

Collier, R. (1931). The Robert Collier Letter Book. New York ; London: McGraw-Hill Book Company.

Citación estilo Chicago

Collier, Robert. The Robert Collier Letter Book. New York ; London: McGraw-Hill Book Company, 1931.

Cita MLA

Collier, Robert. The Robert Collier Letter Book. New York ; London: McGraw-Hill Book Company, 1931.