Bumble Bees in Ohio, OSU bumble bee factsheet
Bumble Bees of the Eastern U.S. (free PDF), The Xerces Society for Invertebrate Conservation
Bumble Bee Watch community science project, The Xerces Society for Invertebrate Conservation
Bumble Bee Books, Links and Papers (compiled as part of the Bumble Bee Short Course)
Conserving Bumble Bees (free PDF), The Xerces Society for Invertebrate Conservation
Native Plants for Pollinators and Beneficial Insects, The Xerces Society