Ezzat, Y.M., & Rawhy, S.H. 1969 Effect of timing and frequency of spraying on the control of the black scale, Chrysomphalus ficus Ashmead, infesting orange trees.. Agricultural Research Review 47(3): 92-110.

Notes: For the control of Chrysomphalus ficus on orange trees, a schedule of two sprays, one in March followed by another in May, is presented as the best treatment.