Literature
- Baldock, D., Wood, T., Cross, I., Smit, J. 2018. The Bees of Portugal (Hymenoptera: Apoidea: Anthophila) – Entomofauna Suppl. S22: 1–164.
- Bieri, S. 2002. Die Bienen und Wespen des Fürstentums Liechtenstein. Amtlicher Lehrmittelverlag.
- Tomozei, B. 2008. Checklist of Bees of the genera Colletes Latreille 1930 and Hylaeus Fabricius 1793 of Romania (Hymenoptera: Apiformes: Colletidae) Faunistic Entomology – Entomologie faunistique 2008 61 (3), 87-97.