Amin, Mohammad, et al. “EFFECT OF PLANTING METHODS, SEED DENSITY AND NITROGEN PHOSPHORUS (NP) FERTILIZER LEVELS ON SWEET CORN (Zea Mays L.)”. Journal of Research (Science), vol. 17, no. 2, July 2006, pp. Pages: 83-89, http://jorscience.com/index.php/JRS/article/view/235.