Pickett, A.D., Putnam, W.L., & LeRoux, E.J. 1958 Progress in harmonizing biological and chemical control of orchard pests in eastern Canada.. Proceedings of the Tenth International Congress of Entomology. Vol. 3. Ottawa 895 pp.

Notes: [Conference held August 17-25, 1956 in Montreal, Canada] Pest species mentioned include Lecanium corni, Lepidosaphes ulmi and Phenacoccus aceris.