Adekayanti, P., Y. W. Subronto, and R. A. Ahmad. “COVID-19 Serological Epidemiology Study at the IG Supermarket Cluster in the Special Region of Yogyakarta”. BKM Public Health and Community Medicine, Vol. 38, no. 03, Mar. 2022, pp. 69-76, doi:10.22146/bkm.v38i03.1787.