Sawaftah, W., & Aljeraiwi, A. (2016). The Effectiveness of Blended Learning Based on Blackboard in Immediate and Delayed Achievement and Retention in a Physics Course among Health Colleges Students at King Saud University (KSU). Journal of Educational and Psychological Studies, 10(3), 476-497. https://doi.org/10.53543/jeps.vol10iss3pp476-497