Namita M. Butale, and Dattatraya.V.Kodavade. “Survey Paper on Detection of Unhealthy Region of Plant Leaves Using Image Processing and Soft Computing Techniques”. International Journal of Computer Engineering in Research Trends, vol. 5, no. 12, Dec. 2018, pp. 232-5, https://www.ijcert.org/index.php/ijcert/article/view/517.