Krawczyk, Marcin, and Mariusz Pociecha. “INFLUENCE OF A 6-WEEK MIXED BALLISTIC-PLYOMETRIC TRAINING ON THE LEVEL OF SELECTED STRENGTH AND SPEED INDICES OF THE LOWER LIMBS IN YOUNG FOOTBALL PLAYERS”. SOCIETY. INTEGRATION. EDUCATION. Proceedings of the International Scientific Conference 4 (May 21, 2019): 198–206. Accessed March 11, 2026. https://archive-journals.rtu.lv/sie/article/view/2194.