Grzegorczyk, Michał, Piotr Kwiatkowski, and Piotr Majcher. 2018. “Subjective Assessment of the Effectiveness of Physiotherapeutic Methods in Lumbosacral Discogenic Pain Syndrome”. Journal of Education, Health and Sport 8 (3):164-92. https://apcz.umk.pl/JEHS/article/view/5341.