Szajnowska-Wysocka, A., and E. Zuzańska-Żyśko. “The Upper-Silesian Conurbation on the Path towards the ‘Silesia’ Metropolis”. Bulletin of Geography. Socio-Economic Series, no. 21, Aug. 2013, pp. 111-24, doi:10.1515/bog-2013-0025.