S. Morita, S. Yamada and J. Abe, “Analysis on Root System Morphology in Rice with Reference to Varietal Differences at Ripening Stage,” Japanese Journal of Crop Science, Vol. 64, 1995, pp. 58-65. doi:10.1626/jcs.64.58
 B. R. Huang, “Water Relations and Root Activities of Buchloe Dactyloides and Zoysia Japonica in Response to Localized Soil Drying,” Plant and Soil, Vol. 208, No. 2, 1999, pp. 179-186. doi:10.1023/A:1004472314631
 C. H. Willium and A. Steinbergs, “Soil Sulphur Fractions as Chemical Indices of Available Sulphur in Some Australian Soils,” Australian Journal of Agricultural Research, Vol. 100, 1959, pp. 340-352.
 N. Uphoff and R. Randriamiharisoa, “Reducing Water Use in Irrigated Rice Production with the Madagascar System of Rice Intensification (SRI),” Proceedings of the International Workshop on Water-Wise Rice Production, IRRI, Los Banos, 2002, pp. 71-87.
 M. D. Shrirame, H. J. Rajgire and A. H. Rajgiri, “Effect of Spacing and Seedling Number per Hill on Growth Attributes and Yield of Rice Hybrids under Lowland Condition,” Journal of Soil and Crops, Vol. 10, No. 1, 2000, pp. 109-113.
 A. Ayalew and T. Dejene, “Combined Application of Organic and Inorganic Fertilizers to Increase Yield of Barley and Improve Soil Properties at Fereze in Southern Ethiopia,” Innovative Systems Design and Engineering, Vol. 3, No. 1, 2012, pp. 25-35.
 S. Mithun, S. S. Mondal, D. Acharya and S. Sanjoy, “Effect of Integrated Nutrient Management on Productivity and Quality of Basmati Rice (Oryza sativa L.),” Oryza, Vol. 44, No. 2, 2007, pp. 125-129.