ERZIN, Alexandr, GAZDOWSKA, Zuzanna & PIOTROWSKA-PÓŁROLNIK, Małgorzata. When “social existence determines consciousness”: the influence of political system on psychological well-being, happiness, proactive coping, and depression levels among Polish and Russian citizens – a cross-cultural study. Journal of Education, Health and Sport [online]. 6 April 2017, T. 7, nr 4, s. 342–359. [accessed 2.6.2023].