Pettey, F.W., & Marais, S.J.S. 1950 The cochineal (Dactylopius opuntiae), and the problem of its control in spineless cactus plantations. Part II. The control of cochineal in spineless cactus plantations.. Entomology Series, Department of Agriculture, Union of South Africa 26: 13-34.

Notes: [Also part of Bulletin No. 296.] Chemical control measures discussed; cactus varieties which tolerate cochineal.