J. Fijał

The decline of the bumble bees and cuckoo bees (Hymenoptera: Apidae: Bombini) of Western and Central Europe

P. Olejniczak, W. Solarz, W. Król, 2007, Oryx.

Psithyrus flavidus (EVERSMANN) (Hymenoptera: Apoidea: Apidae) in Poland

A. Kosior, W. Celary, J. Fijał, 2003 .

Long-term changes in the species composition and distribution of Bombini (Apidae) in Cracow since the mid 1850s

W. Solarz, P. Rasmont, Z. Witkowski, 2008 .