Cita APA (7th ed.)

Leedy, P. D. (1992). Practical research planning and desing (5a. ed.). MacMillan.

Cita Chicago (17th ed.)

Leedy, Paul D. Practical Research Planning and Desing. 5a. ed. Nueva York: MacMillan, 1992.

Cita MLA (9th ed.)

Leedy, Paul D. Practical Research Planning and Desing. 5a. ed. MacMillan, 1992.