Müller-Frączek, Iwona, Joanna Muszyńska, and Michał Bernard Pietrzak. 2013. “Analysis of Convergence Process of Polish Household Food Expenditures”. Acta Universitatis Lodziensis. Folia Oeconomica, no. 293 (January):63-73. https://doi.org/10.18778/0208-6018.293.06.