Biddle, B. J., & Ellena, W. J. (1964). Contemporary research on teacher effectiveness: Bruce J. Biddle [and others]. Holt, Rinehart and Winston.
Lua i Stíl Chicago (17ú heag.)Biddle, Bruce J., agus William J. Ellena. Contemporary Research on Teacher Effectiveness: Bruce J. Biddle [and Others]. New York: Holt, Rinehart and Winston, 1964.
Lua MLA (9ú heag.)Biddle, Bruce J., agus William J. Ellena. Contemporary Research on Teacher Effectiveness: Bruce J. Biddle [and Others]. Holt, Rinehart and Winston, 1964.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.