Simmonds, F.J., & Greathead, D.J. 1977 Introductions and pest and weed problems.. Origins of Pest, Parasite, Disease and Weed Problems. Blackwell Scientific Oxford 413 pp.
Notes: [The 18th Symposium of The British Ecological Society, Bangor, 12-14, April 1976.] Icerya purchasi is mentioned as an example of an insect pest that spreads to new countries on its host. Aonidiella aurantii is an example of an insect pest that has replaced A. aurantii in parts of California.