Guba V.P., Levushkin S.P., and Lyakh V.I. “Approaches to the Study of Progress, Monitoring of Sports Training and Selection of Athletes in a Sports Context”. Theory and Practice of Physical Culture, no. 9 (October 5, 2025): 3–7. Accessed December 5, 2025. http://www.tpfk.ru/index.php/TPPC/article/view/1444.