Andigena hypoglauca hypoglauca - Grey-breasted Mountain-toucan

W. S. 1924. Auk: 41(2): 368.
Chapman on New South American Birds

Parker, T. A., III and J. P. O'neill. 1980. Auk: 97(1): 167-176.
Notes on Little Known Birds of the Upper Urubamba Valley, Southern Peru

Graves, G. R. 1985. Auk: 102(3): 556-579.
Elevational Correlates of Speciation and Intraspecific Geographic Variation in Plumage in Andean Forest Birds

Davis, T. J. 1986. Condor: 88(1): 50-56.
Distribution and Natural History of Some Birds from the Departments of San Martin and Amazonas, Northern Peru

Lanyon, S. M. and R. M. Zink. 1987. Auk: 104(4): 724-732.
Genetic Variation in Piciform Birds: Monophyly and Generic and Familial Relationships

Remsen, J. V., Jr., M. A. Hyde and A. Chapman. 1993. Condor: 95(1): 178-192.
The Diets of Neotropical Trogons, Motmots, Barbets and Toucans