Nałęcz, H., A. Ostrowska-Tryzno, and A. Pawlikowska-Piechotka. “Outdoor Gyms As an Example of Outdoor Recreation Activity in Urbanized Areas”. Turyzm/Tourism, vol. 28, no. 1, June 2018, pp. 65-71, doi:10.18778/0867-5856.28.1.16.