Gaczek, Wanda Maria. “Geographical Proximity As a Factor of Growth in Sub-Regions of Big Cities in Poland”. Studia Oeconomica Posnaniensia 3, no. 8 (August 31, 2015): s. 7–29. Accessed September 3, 2026. https://journals.ue.poznan.pl/soep/article/view/3983.