Raghavaiah, C V, I.Y.L.N Murthy, and S Riazuddin Ahmed. 2008. “Soil Test Crop Response Calibration Studies on Rainfed Castor (Ricinus Communis) in Alfisols*”. The Indian Journal of Agricultural Sciences 78 (9). https://epubs.icar.org.in/index.php/IJAgS/article/view/9951.