Cita APA (7a ed.)

Wagner, V., Weeks, G. R., & L'Abate, L. (1980). Enrichment and written messages with couples. [s.n.].

Cita Chicago Style (17a ed.)

Wagner, Victor, Gerald R. Weeks, y Luciano L'Abate. Enrichment and Written Messages with Couples. [S.l.]: [s.n.], 1980.

Cita MLA (9a ed.)

Wagner, Victor, et al. Enrichment and Written Messages with Couples. [s.n.], 1980.