Jhangiani, R. S., & Jhangiani, S. (2017). Investigating the Perceptions, Use, and Impact of Open Textbooks: A survey of Post-Secondary Students in British Columbia. The International Review of Research in Open and Distributed Learning, 18(4).
I found this study insightful because it shows that high textbook costs affect student engagement and performance. Using open textbooks not only saves money but also allows students to access materials instantly.