Kotlińska, Janina, Jarosław Kuśpit, Zdzisław A. Błasiak, and Grzegorz Kotliński. “Sources and Methods of Gathering Economic Information by Household Members”. Journal for Perspectives of Economic Political and Social Integration 31, no. 1 (December 30, 2025): 155–187. Accessed January 11, 2026. https://czasopisma.tnkul.pl/index.php/jpepsi/article/view/4615.