Catalogue of British Hymenoptera in the British Museum. Part 1, Andrenidae and Apidae.
London:Printed by order of the Trustees,1891
Public domain. The BHL considers that this work is no longer under copyright protection.
Evidence reported by Marlete Kurten for item catalogueofbrit0brituoft on March 11, 2008: no visible notice of copyright; stated date is 1891.