Attributes / relations provided by
♦ 1del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.).
Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
♦ 2OIL-COLLECTING BEES AND RELATED PLANTS: A REVIEW OF THE STUDIES IN THE LAST TWENTY YEARS AND CASE HISTORIES OF PLANTS OCCURRING IN NE BRAZIL, Isabel Cristina Machado, Solitary Bees Conservation, Rearing and Management for Pollination, International Workshop on Solitary Bees and Their Role in Pollination, held in Beberibe, Ceará, Brazil, in April 2004, pp. 255-280