Shenefelt, R.D., & Benjamin, D.M. 1955 Insects of Wisconsin forests.. Circular (University of Wisconsin, College of Agriculture, Extension Service) No. 500: 1-110.
Notes: Scale species reviewed include Toumeyella numismaticum, Lepidosaphes ulmi, Aspidiotus perniciosus, Gossyparia spuria and cottony maple scale.