Podstawka, Marian, and Bartłomiej Suchodolski. “Measurement and Assessment of the Level of Economic Development of the Counties of the Opolskie Voivodeship”. Management and Administration Journal 47, no. 120 (August 2, 2019): 25–32. Accessed December 22, 2024. https://czasopisma.uws.edu.pl/znadministracja/article/view/780.