Weigel, C.A., & Sasscer, E.R. 1923 Insects injurious to ornamental greenhouse plants.. Farmer's Bulletin (United States Department of Agriculture) No. 1362: 76+ pp.

Notes: Species mentioned include Pseudococcus citri, P. adonidum and Orthezia insignis as well as scales identified by common name (aspidistra, black, Boisduval's box, camellia, cyanophyllum, Florida red, greedy, ivy or oleander, latania, long soft, Morgan's, orchid, pineapple, proteus, red or orange, soft brown, tessellated, thread and zamin.