Spyrydonov, V.G., and M.D. Melnychuk. “Coronavirus S Antigen As a Marker of Effective Vaccination”. Reports of the National Academy of Sciences of Ukraine, no. 3 (July 6, 2021): 96–103. Accessed April 21, 2025. https://nasu-periodicals.org.ua/index.php/dp/article/view/2021-3-13.