Cook, T. D., & Campbell, D. T. (1979). Quasi-experimentation: Design & analysis issues for field settings. Houghton Mifflin.
Lua i Stíl Chicago (17ú heag.)Cook, Thomas D., agus Donald Thomas Campbell. Quasi-experimentation: Design & Analysis Issues for Field Settings. Boston: Houghton Mifflin, 1979.
Lua MLA (9ú heag.)Cook, Thomas D., agus Donald Thomas Campbell. Quasi-experimentation: Design & Analysis Issues for Field Settings. Houghton Mifflin, 1979.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.