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.
♦ ²Insights on small cetacean feeding habits in southeastern Brazil, Marcos César de Oliveira Santos, Sergio Rosso, Roberta Aguiar dos Santos, Silvia Helena Bulizani Lucato, and Manuela Bassio, Aquatic Mammals 2002, 28.1, 38-45