Tolong jelaskan mengenai Sumber dari Bombus

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Anon. "Bees". World Book Encyclopedia, 1998 ed.

Benton, Ted. Bumblebees. New Naturalist Series (#98). Collins, 2006.

Freeman, Scott. Biological Science. Upper Saddle River, 2002.

Goulson, Dave. Bumblebees: Their Behaviour and Ecology, 2003. Oxford University Press. .

Goulson, Dave. A Sting in the Tale. Jonathan Cape, 2013.

Hasley, William D. "Bees". Collier's Encyclopedia, 1990 ed.

Macdonald, Murdo. Bumblebees. Scottish Natural Heritage, 2003.