Ertmer, P. A., & Newby, T. J. (1993). Behaviorism, cognitivism, constructivism: Comparing critical features from an instructional design perspective. Performance Improvement Quarterly, 6(4), 59-71. Retrieved from http://sylvan.live.ecollege.comАрхивирано на сајту Wayback Machine (18. март 2018)
Ertmer, P. A., & Newby, T. J. (1993). Behaviorism, cognitivism, constructivism: Comparing critical features from an instructional design perspective. Performance Improvement Quarterly, 6(4), 59-71. Retrieved from http://sylvan.live.ecollege.comАрхивирано на сајту Wayback Machine (18. март 2018)