Demidov, V., V. Sivkov, A. Nazarenko, V. Demidova, and F. Mavliev. “ANAEROBIC PERFORMANCE AND MORPHOLOGICAL DEVELOPMENT OF YOUNG FOOTBALL PLAYERS DURING THE INITIAL PREPARATION STAGE”. Human. Sport. Medicine, Vol. 19, no. 4, Jan. 2020, pp. 20-28, doi:10.14529/hsm190403.