N. NARESH and S.CHANDER RAO, M. SANTHA LAKSHMI PRASAD*, K. SUJATHA,. “Variability in Sclerotium Rolfsii Associated With Collar Rot of Sunflower”. Indian Phytopathology, vol. 65, no. 2, May 2012, pp. 161-5, https://epubs.icar.org.in/index.php/IPPJ/article/view/18580.