MATOŠKOVÁ, Dagmar. Competitiveness in the production of selected crops from the perspective of variable costs. In Agricultural economics : an international journal = mezinárodní vědecký časopis. - Prague : Institute of Agricultural and Food Information, 2004. ISSN 0139-570X, 2004, vol. 50, no. 11, s. 514-523. Dostupné na : <http://www.agriculturejournals.cz/publicFiles/58793.pdf>