Dimitrov, T. 1935 [Contribution to the study of damage caused by insects and fungi parasites in the Bulgarian forests.]. Annals of the University of Sofia 13: 220-252.

Notes: Summary in French; species mentioned include Aspidiotus salicis, Chermes abietis, Ch. viridis, Eulecanium robiniarum, Gossyparia ulmi, Lecanium aceris, L. carpini, L. fraxini, Lachnus sp., and Lepidosaphes ulmi.