Swain, A.F., & Buckner, R.P. 1940 Toxicity of hydrocyanic acid to eggs of black scale (Saissetia oleae (Bern.)).. Journal of Economic Entomology 33(1): 107-111.

Notes: The difference in susceptibility to HCN of black scale from different localities isn't carried over into the eggs. Furthermore, there is evidence that there is a high toxicity to the eggs of HCN at concentrations usable in field fumigation. Satisfactory control of "resistant" black scale might be secured by earlier season fumigation.