Cita APA (7a ed.)

Ledford, C. C., & Warren, L. L. (1997). Cooperative learning: Perceptions of presevice teachers. [s.n.].

Cita Chicago Style (17a ed.)

Ledford, Carolyn C., y Louis L. Warren. Cooperative Learning: Perceptions of Presevice Teachers. [S.l.]: [s.n.], 1997.

Cita MLA (9a ed.)

Ledford, Carolyn C., y Louis L. Warren. Cooperative Learning: Perceptions of Presevice Teachers. [s.n.], 1997.