Cozby, P. C. (1989). Methods in behavioral research (4th ed.). Mayfield.
Lua i Stíl Chicago (17ú heag.)Cozby, Paul C. Methods in Behavioral Research. 4th ed. California: Mayfield, 1989.
Lua MLA (9ú heag.)Cozby, Paul C. Methods in Behavioral Research. 4th ed. Mayfield, 1989.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.