Tkocz, Maria, and Arkadiusz Heder. “Innovative Activities in a Failing Industrial Trade Based on the Example of the Coal Mining Industry”. Studies of the Industrial Geography Commission of the Polish Geographical Society 20 (January 1, 2012): 134–146. Accessed November 21, 2024. https://prace-kgp.uken.krakow.pl/article/view/394.