“Effects of Prilled Urea, Farmyard Manure and Azotobater on the cotton– Wheat Cropping System for Realizing Higher Yield Potential on Ustochrepts of Indo-Gangetic Plain. (108)”. Tropical Agriculture, vol. 87, no. 3, July 2010, https://journals.sta.uwi.edu/ojs/index.php/ta/article/view/1042.