Yamunah Vaicondam et al. 2022. Research Landscape of Digital Learning Over the Past 20 Years: A Bibliometric and Visualisation Analysis. International Journal of Online and Biomedical Engineering (iJOE). 18, 08 (Jun. 2022), pp. 4–22. DOI:https://doi.org/10.3991/ijoe.v18i08.31963.