Kalbarczyk, Małgorzata, and Joanna Mackiewicz-Łyziak. “Ageing Population, Physical Activity, and Long-Term Fiscal Sustainability: Evidence from Poland ”. Studia Demograficzne, no. 1(177) (December 30, 2020): 107–122. Accessed November 22, 2024. https://econjournals.sgh.waw.pl/SD/article/view/2522.