Klassen, Robert M., Sündüs Yerdelen, and Tracy L Durksen. “Measuring Teacher Engagement: Development of the Engaged Teachers Scale (ETS)”. Frontline Learning Research 1, no. 2 (December 18, 2013): 33–52. Accessed June 26, 2026. https://www.frontlinelearningresearch.org/flr/index.php/journal/article/view/44.