Reference
Eva-Maria Levermann, Inge Bischoff, Thomas Wagner (2000): Species-specific foraging strategies of the syntopical and synchronous bees Panurgus calcaratus (SCOPOLI, 1763) and Dasypoda hirtipes (Fabricius), 1793 – Beiträge zur Entomologie = Contributions to Entomology – 50: 179 - 191.