APA

Mandino O., . (1968). The greatest salesman in the world. New York: F. Fell.

Chicago

Mandino Og, . 1968. The greatest salesman in the world. New York: F. Fell.

Harvard

Mandino O., . (1968). The greatest salesman in the world. New York: F. Fell.

MLA

Mandino Og, . The greatest salesman in the world. New York: F. Fell. 1968.