Richards, O. W. 1956. Hymenoptera. Introduction and key to families. Handbooks for the Identification of British Insects 6(1):1-94.

Bolton, B.; Collingwood, C. A. 1975. Handbooks for the identification of British Insects. Hymenoptera, Formicidae. Handbooks for the Identification of British Insects 6(3(c)):1-34.

Richards, O. W. 1977. Hymenoptera. Introduction and key to families. Handbooks for the Identification of British Insects 6(1)(2nd edn.):1-100.