Olejnik, Alicja Anna. “Returns to Scale for EU Regions – Evidence from the Spatial Panel Model”. Acta Universitatis Lodziensis. Folia Oeconomica 3, no. 329 (September 22, 2017): [23]-32. Accessed December 6, 2025. https://www.czasopisma.uni.lodz.pl/foe/article/view/805.