Avdeev, Y. I., V. V. Arsen’ev, and V. N. Naidenko. ’Extremism in Modern Russia: Sourses, Content, Typology’. Sociologicheskaja Nauka I Social’naja Praktika, no. 2, Oct. 2015, pp. 108-22, https://www.jour.fnisc.ru/index.php/socnp/article/view/2957.