PsycLearn Research Methods Version 1.4 (2020). CogBooks, American Psychological Association. Module 9: Between Group and Within Group Research Designs
This resource is linked in the course.
Greenwald, A. G. (1992). Within-subjects designs: To use or not to use? In A. E. Kazdin (Ed.), Methodological issues & strategies in clinical research (pp. 157–167). American Psychological Association.