Chkhartishvili, Alexander, Dmitry Gubanov, and Ivan Kozitsin. 2021. “Face Mask Perception During the COVID-19 Pandemic: An Observational Study of Russian Online Social Network VKontakte”. Advances in Systems Science and Applications 21 (3), 91-100. https://doi.org/10.25728/assa.2021.21.3.1124.