Elmurzaev, M. ., S.-A. . Aslakhanov, N. . Zinoviev, and N. Alekseeva. “BASIC AND ASSOCIATED CATEGORIES OF PHYSICAL RECREATION”. 2023. Theory and Practice of Physical Culture, no. 3, Apr. 2023, pp. 50-51, http://tpf1610220.nichost.ru/index.php/TPPC/article/view/492.