Cita APA (7a ed.)

Hoover, S. R. (1921). The science and art of salesmanship. MacMillan.

Cita Chicago Style (17a ed.)

Hoover, Simon Robert. The Science and Art of Salesmanship. New York: MacMillan, 1921.

Cita MLA (9a ed.)

Hoover, Simon Robert. The Science and Art of Salesmanship. MacMillan, 1921.