Cita APA (7a ed.)

Poppe, F. C. (1988). 50 rules to keep a client happy. Harper & Row.

Cita Chicago Style (17a ed.)

Poppe, Fred C. 50 Rules to Keep a Client Happy. New York [etc.]: Harper & Row, 1988.

Cita MLA (9a ed.)

Poppe, Fred C. 50 Rules to Keep a Client Happy. Harper & Row, 1988.