Hopkinson, J. 1904 Some Hertfordshire scale-insects.. Transactions, Hertfordshire National History Society and Field Club 12: 49-52.

Notes: Scale species mentioned include Parlatoria pergandii, P. zizyphi, Aspidiotus, Mytilaspis pomorum, Lichtensia viburnia, Coccus cacti, Kermes, Tachardia lacca, Ericerus pela, Ceroplastes ceriferus, Lecanium bituberculatum, L. capreae, L. persicae, Asterolecanium fraxini, Cryptococcus cistudiformis, C. fagi, Apterococcus fraxini and Dactylopius citri.