Ziętara, Wojciech, and Marek Zieliński. “COMPETITIVENESS OF POLISH AND GERMAN FARMS SPECIALIZED IN FIELD CROPS”. Journal of Agribusiness and Rural Development 53, no. 3 (October 8, 2019): 281–290. Accessed April 26, 2024. http://www1.up.poznan.pl/jard/index.php/jard/article/view/1261.