Cita APA (7a ed.)

Montada, L., Bierhoff, H., & Bierhoff, H. (1991). Altruism in social systems. Hogrefe.

Cita Chicago Style (17a ed.)

Montada, Leo, Hans-Werner Bierhoff, y Hans-Werner Bierhoff. Altruism in Social Systems. Lewiston, NY Stuttgart [u.a.]: Hogrefe, 1991.

Cita MLA (8a ed.)

Montada, Leo, et al. Altruism in Social Systems. Hogrefe, 1991.