@article {1755,
	title = {Contribution to the taxonomy of the Hylaeus gibbus species group in Europe (Hymenoptera, Apoidea and Colletidae).},
	journal = {Zootaxa},
	volume = {2932},
	year = {2011},
	pages = {51-67},
	author = {J. Straka and P. Bogusch}
}
