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.
♦ 2Beissinger, SR, Thomas, BT and Strahl, SD (1988)
Vocalizations, food habits, and nesting biology of the Slender-billed Kite, with comparisons to the Snail Kite Wilson Bull. 100: 604-616