1. Bandelt HJ, Forster P, Röhl A (1999) Median-joining networks for inferring intraspecific phylogenies. Mol Biol Evol 16:37–48
2. Berezin MV (1989) The infestation of bumble bees by the nematode Sphaerularia bombi in the Wrangel Island. In: Chernov YuI, Getsen MV, Tishkov AA (eds) Interactions between organisms in the tundra ecosystems. The All-Union Workshop, Syktyvkar, pp 102–103
3. Berezin MV (1990) Ecology and nesting of bumblebees on Wrangel Island. Proc Colloq of All-Union Entomol Soc Section for the Study of Social Insects, 1st edn. Colloquium, Leningrad, pp 19–28
4. Berezin MV (1992) Interactions between bumble bees and polar foxes in the Wrangel Island. In: Chernov YuI (ed) Coenotic interactions in tundra ecosystems. A Collection of Scientific Papers. Nauka, Moscow, pp 90–99
5. Berezin MV (1994) Social organization of the bumble bees (Hymenoptera, Apidae, Bombus) in the Arctic (Wrangel Island). In: Lenoir A, Arnold G, Lepage M (eds) Les insectes sociaux. The 12th congress of the international union for the study of soc insects IUSSI. University Paris Nord, Paris, p 320