Reference

V. A. Alekseyev (1982): A study on bumble bees in the Experimental Farm of the Yaroslavl Insti-tute for Cattle-Breeding and Fodder-Production; [Ru; 6 refs. Date: 23.VI.1982]. – In: GREBENNIKOV, V. S. (ed.). Insect Pollinators of Agricultural Plants. A Collection of Scientific Papers. Novosibirsk (Siberian Branch of the V. I. LENIN All-Union Academy of Agricultural Sciences) – : 105 - 110.