BioStor
 | Catalogue of Hymenoptera in the collection of the Entomological Society of Philadelphia, from Colorado Territory. [concl E T Cresson (1865) ] Proceedings of the Entomological Society of Philadelphia 4: 426-488 |
 | Ecological-behavioral studies of the wasps of Jackson Hole, Wyoming H E Evans (1970) Bulletin of The Museum of Comparative Zoology 140: 451-511 |
 | An exploratory analysis of cladistic relationships within the superfamily Apoidea, with special reference to sphecid wasps (Hymenoptera) B A Alexander (1992) Journal of Hymenoptera Research 1: 25-61 |