Kumar, R. L. B. D. “Effect of Varying Levels of Nitrogen on Growth, Yield, Quality and Profitability of Transplanted Fennel (Foeniculum Vulgare Mill.)”. Journal of Spices and Aromatic Crops, vol. 25, no. 2, Dec. 2016, pp. 141-8, https://updatepublishing.com/journal/index.php/josac/article/view/5179.