MIERZEJEWSKA, Lidia and PARYSEK, Jerzy J. Regional differences in the age structure of Poland’s population in the years 1999–2010: a multivariate approach. Bulletin of Geography. Socio-economic Series. Online. 18 March 2013. No. 19, p. 61–72. [Accessed 25 December 2025]. DOI 10.1515/bog-2013-0004.