D. H. Al.Zobaidy, M. A. Mohammed, S. Sergiwa, and O. A. Abugela, “A Study of Knowledge-level by Some Pests Affecting on Apple Trees and Methods of their Control, for Farmers in Some Regions Shabiat AL Gabal Alaktar”, MJSc, vol. 8, no. 1, pp. 23–9, Dec. 2001.