Niewiadomski, Kazimierz. “Directions of Development for Areas With Unfavourable Conditions for Agricultural Production, an Example of the Podlaskie Voivodeship (Poland)”. Journal of Agribusiness and Rural Development 23, no. 1 (December 31, 2012): 71-84. Accessed April 27, 2024. http://www1.up.poznan.pl/jard/index.php/jard/article/view/504.