Blumberg, D., & Mendel, Z. 1991 [Improvement of the biological control of the cottony cushion scale Icerya purchasi by the parasitic fly, Cryptochetum iceryae.]. Hassadeh 71: 1107-1112.

Notes: Rodolia cardinalis had become less effective at controlling I. purchasi; C. iceryae and Rodolia iceryae collected in South America and released at sveral sites planted with Erythrina corallodendrum, Spartium junceum or Retama raetam infested with I. purchasi, although populations sparse; suppression of the scale achieved in two years.