Cita APA (7th ed.)
Bertcher, H. J. (1979). Group participation. Sage.
Cita Chicago (17th ed.)
Bertcher, Harvey J. Group Participation. London: Sage, 1979.
Cita MLA (9th ed.)
Bertcher, Harvey J. Group Participation. Sage, 1979.
Atenció: Aquestes cites poden no estar 100% correctes.