Borkowska, M., and M. Kruszyński. “KNOWLEDGE ABOUT CROSS-COMPLIANCE POSSESSED BY FARMERS FROM OPOLSKIE VOIVODSHIP”. Acta Scientiarum Polonorum. Oeconomia, vol. 11, no. 4, Dec. 2012, pp. 5-13, https://aspe.sggw.edu.pl/article/view/549.