Azad, H., Amin, M., Tithi, D. and Hossain, S. 2012. Performances of Three Cotton Varieties Cultivated under Economic Threshold Level Based Insecticide Sprayed and Non-Sprayed Conditions. Our Nature. 9, 1 (Jan. 2012), 21–25. DOI:https://doi.org/10.3126/on.v9i1.5728.