Family Megachilidae - Leafcutter, Mason, and Resin Bees, and allies
Phylogeny of the bee family Megachilidae (Hymenoptera: Apoidea) based on adult morphologyBy Gonzalez V.H., Griswold T.L., Praz C.J., Danforth B.N.
Syst. Entomol. 37: 261-286, 2012
Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associa...By Victor H. Gonzalez , Terry L. Griswold
Zoological Journal of the Linnean Society, Vol. 168(2), pp. 221–425, 2013
This is an outstanding reference covering New World members of the genus Anthidium
The full title is:
"Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography"
The 200+ page revision can be:
1) Freely viewed online at the URL: https://academic.oup.com/zoolinnean/article/168/2/221/2433440/Wool-carder-bees-of-the-genus-Anthidium-in-the
Leafcutter and Mason Bees of the Genus Megachile Latreille (Hymenoptera: Megachilidae) in Canada and AlaskaBy Sheffield, Cory S. et al.
Canadian Journal of Arthropod Identification, 2011
"Our objective is to provide an up-to-date revision of the genus Megachile of this region, including an interactive key to the species, and summaries of biogeographic distribution and life history."
HTML version online
The Pollen-Collecting Bees of the Anthidiini of California (Hymenoptera: Megachilidae)By Grigarick, A. A. and L. A. Stange
Bulletin of the California Insect Survey, University of California, 1968
Text of 113 pages, with 41 maps and 227 figures at the end of the paper.