Георгієва [Nadezhda Georgieva] Н. Г. Influence modern fitness of the systems on motivation to employments of physical culture of teenagers of task medical force. Slobozhanskyi Herald of Science and Sport, [S. l.], n. 5(38), p. 59–63, 2013. Disponível em: https://journals.uran.ua/index.php/1991-0177/article/view/20219. Acesso em: 13 may. 2024.