BioStor
 | The entomology of the Mid-Alpine zone of Custer County Colorado Cockerell T.d.a. (1893) Transactions of the American Entomological Society 20: 305-370 |
 | The Bees of New Mexico T D A Cockerell (1906) Transactions of The American Entomological Society 32: 289-314 |
 | The bees of the Rooky mountain national park (1919) Entomological News Philadelphia 30: 286-294 |
 | Descriptions and records of bees, lxxxvii (1919) Annals And Magazine of Natural History 4: 355-360 |
 | Biology And Subgeneric Placement Of Osmia pikei (Hymenoptera, Megachilidae) C Cripps and R W Rust (1985) Entomological News 96: 109-113 |
 | Urban Bee Diversity in a Small Residential Garden in Northern California Gordon W Frankie, Robbin W Thorp et al. (2009) Journal of Hymenoptera Research 18: 368-379 |