Cita APA (7th ed.)

Carhuff, R. R. (1980). The art of helping IV. Human Resource Development Press.

Cita Chicago (17th ed.)

Carhuff, Robert R. The Art of Helping IV. Amherst, MA: Human Resource Development Press, 1980.

Cita MLA (9th ed.)

Carhuff, Robert R. The Art of Helping IV. Human Resource Development Press, 1980.