Cita APA (7th ed.)
Collins, G. R. (1976). How to be a people helper. Vision House Publishers.
Cita Chicago (17th ed.)
Collins, Gary R. How to Be a People Helper. Santa Ana, Calif.: Vision House Publishers, 1976.
Cita MLA (9th ed.)
Collins, Gary R. How to Be a People Helper. Vision House Publishers, 1976.
Atenció: Aquestes cites poden no estar 100% correctes.