J. H.  Cane and Tepedino, V. J., ?Causes and extent of declines among native North American invertebrate pollinators: Detection, evidence, and consequences?, Conservation Ecology, vol. 5, pp. 17 - 26, 2001.

J. H.  Cane, ?Habitat fragmentation and native bees: a premature verdict??, Conservation Ecology, vol. 5, pp. 149 - 161, 2001.