Table 1.

Summary of the research question, strategies, and bibliometric techniques.

RO	Description	Strategy to answer RQ	Technique
1	To identify central articles that provide a significant impact on e-learning in higher education during the COVID-19 pandemic.	To identify articles in HEIs e-learning adoption during COVID-19 with the highest citation	Citation analysis
2	To explore the structure of e-learning adaptation in higher education institutions.	The emergence issue discussed on the relationship among the most co-cited documents	Co-citation analysis
3	To comprehend the evolution of e-learning by identifying the linkages among central articles and the evolution of such linkages over time.	Evaluate the keywords with the highest frequency and relations among the clusters	Co-occurrence of keyword analysis