Boratyński, K.L., & Davies, R.G. 1971 The taxonomic value of male Coccoidea (Homoptera) with an evaluation of some numerical techniques.. Biological Journal of the Linnean Society 3: 57-102.

Notes: Taxonomic value of characters reviewed in relation to traditional classification based on females; numerical methods applied to classification of some Diaspididae; techniques compared and evaluated.