Elliott, M., K. Pernezny, A. Palmateer, and N. Havranek. “Guidelines to Identification and Management of Plant Disease Problems: Part I. Eliminating Insect Damage and Abiotic Disorders: PP248/MG441, 2/2008”. EDIS, vol. 2008, no. 2, Feb. 2008, doi:10.32473/edis-mg441-2008.