1.
PROSKURA, Patrycja and WITKOWSKI, Kazimierz. The law on sport in the light of the opinion of the fitness instructors and personal trainers. Quality in Sport. Online. 24 June 2017. Vol. 3, no. 1, pp. 36-47. [Accessed 19 December 2025]. DOI 10.12775/QS.2017.004.