Smith, H.S., Flanders, S.E., & Basinger, A.J. 1945 The control of Saissetia oleae by Metaphycus helvolus (Compere).. Monthly Bulletin, California Department of Agriculture 34(2): 93-94.
Notes: This experiment tracks the populations of these two species in a citrus- and olive-growing region of California. The infestation was reduced from heavy to light during the years between 1940 through 1944.