Hamilton, C.C. 1936 The identification of insect injury.. National Shade Tree Conference 12th: 150-160.

Notes: Proceedings of an annual meeting; scale species mentioned attacking elm include Aspidiotus perniciosus, A. ancylus, A. juglans-regia, Chionaspis americana, Ch. furfura, Lepidosaphes ulmi, Lecanium corni, Gossyparia spuria and Pulvinaria vitis.