Attributes / relations provided by
♦ ¹Ben-Dov, Y., Miller, D.R. & Gibson, G.A.P. ScaleNet 4 November 2009
♦ ²del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.