Chowdhury, MA Zilani, et al. “Assessment of Self-Incompatibility in Some Improved and Traditional Cultivars of Oleiferous (<i>Brassica rapa< I> L.)”. Bangladesh Journal of Agricultural Research, vol. 32, no. 2, Aug. 2007, pp. 235-46, https://www.banglajol.info/index.php/BJAR/article/view/306.