Krawiec, M. “DESCRIPTION AND PRICING OF SELECTED TWO-ASSET OPTIONS AND SUGGESTIONS CONCERNING THEIR USE ON THE GRAIN MARKET IN POLAND”. Acta Scientiarum Polonorum. Oeconomia, Vol. 12, no. 2, June 2013, pp. 37-53, https://js.wne.sggw.pl/index.php/aspe/article/view/4079.