Turnbull, A.L., & Chant, D.A. 1961 The practice and theory of biological control of insects in Canada.. Canadian Journal of Zoology 39: 697-753.

Notes: The success or failure of each of 31 Canadian biological control projects is assessed. Species listed include Eulecanium coryli, Lepidosaphes ulmi, Phenacoccus aceris, Pseudococcus citri and P. maritimus.