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2. An exploratory analysis of cladistic relationships within the superfamily Apoidea, with special reference to sphecid wasps (Hymenoptera).;Alexander;Journal of Hymenoptera Research,1992
3. Phylogenetic studies of the families of short-tongued bees (Hymenoptera: Apoidea).;Alexander;University of Kansas Science Bulletin,1995
4. Ovaries, ovarioles, and oocytes in parasitic bees (Hymenoptera: Apoidea).;Alexander;Pan-Pacific Entomologist,1987
5. Phylogeny of colletid bees (Hymenoptera: Colletidae) inferred from four nuclear genes.;Almeida;Molecular Phylogenetics and Evolution,2009