Padło, Tomasz. “Three-Sector Division of the European Economy in the Perception of the Inhabitants”. Studies of the Industrial Geography Commission of the Polish Geographical Society 31, no. 3 (September 27, 2017): 244–253. Accessed April 18, 2024. https://prace-kgp.uken.krakow.pl/article/view/20801653.313.16.