S. A. Siadat, M. R. Moradi-Telavat, G. Fathi, M. Mazarei, K. Alamisaeid, and S. H. Mousavi, “Rapeseed (Brassica napus L. var. oleifera) response to nitrogen fertilizer following different previous crops”, Ital J Agronomy, vol. 6, no. 4, p. e31, Nov. 2011.