Cynarski, W.J., P. Pawelec, J.-H. Yu, J. Slopecki, G. Bielec, and K. Kubala. “Young People Practicing Martial Arts and Their Perception of Success”. Pedagogics, psychology, medical-biological problems of physical training and sports 22, no. 5 (September 30, 2018): 231-236. Accessed June 26, 2019. https://sportpedagogy.org.ua/index.php/PPS/article/view/960.