González-Varo J., Biesmeijer J., Bommarco R., Potts S., Schweiger O., Smith H., Steffan-Dewenter I., Szentgyörgyi H., Woyciechowski M., Vilà M. (2013) Combined effects of global change pressures on animal-mediated pollinationTrends in Ecology & Evolution 28(9): 524-530. http://www.sciencedirect.com/science/article/pii/S0169534713001274