SHARMA, M P, et al. “Soil Fertility and Productivity of Rice (Oryza Sativa)-Wheat (Triticum Aestivum) Cropping System in an Inceptisol As Influenced by Integrated Nutrient Management”. The Indian Journal of Agricultural Sciences, vol. 71, no. 2, Apr. 2014, https://epubs.icar.org.in/index.php/IJAgS/article/view/39516.