Huynh, Nhi, Dai Nguyen, Nguyen Ta, Minh Nguyen, Tai Nguyen, Huy Dang, Tuyen Vo, and Ngoan Le. “COVID-19 Clusters at Workplaces and Its Transmission into Communities in Vietnam: A Novel Emerging Occupational Risk Factor at Work Due to Coronavirus Infection”. Asian Pacific Journal of Environment and Cancer 3, no. 1 (August 15, 2020): 27-33. Accessed December 1, 2021. http://waocp.com/journal/index.php/apjec/article/view/530.