Solovey, Olexandr, Valeriy Hunchenko, Dmytro Solovey, and Krzysztof Wnorowski. “Influence of Static Balances Level on Competitive Performance Indicators of Athletes 17-21 Years Old in Beach Volleyball”. Physical education of students 24, no. 6 (December 30, 2020): 332-339. Accessed February 28, 2021. https://sportedu.org.ua/index.php/PES/article/view/1298.