Reference:

Stanisavljevic, L., 2005. The accompanying fauna of Osmia cornuta and Osmia rufa and effective measures of protection. Bulletin of Insectology, 58(2), 141-152.

URL:

https://www.researchgate.net/publication/209780300_The_accompanying_fauna_of_Osmia_cornuta_and_Osmia_rufa_and_effective_measures_of_protection

---