1. Astin, A. (1984). Student involvement: A developmental theory for higher education. Journal of College Student Personnel, 25, 518-529.
2. Azarias, R. A. (2020). Language Needs of Industrial-Technical Teachers in Using English as a Medium of Instruction (unpublished dissertation). Benguet State University.
3. Azarias, R. A., & Vidal, C. A. (2017). Attitude towards ICT course [Undergrad Thesis, Ilocos Sur Polytechnic State College Santiago Campus).
4. COVID-19 and online teaching in higher education: A case study of Peking University;Bao;Human Behavior and Emerging Technologies 2,2020
5. Barto, A. (2020). What is Asynchronous Learning? Less Than 100 Words. Roundtable Learning. https://roundtablelearning.com/what-is-asynchronous-learning-less-than-100-words/