APA aipamena

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

Chicago Style aipamena

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

MLA aipamena

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

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