Koltunov, J. “Cluster Characteristic Structure of Society - the Basis of Mathematical Sociology”. Visnyk of V. N. Karazin Kharkiv National University. Series "Sociological Studies of Contemporary Society: Methodology, Theory, methods", no. 1053, Aug. 2019, pp. 76-85, https://periodicals.karazin.ua/ssms/article/view/13703.