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.
♦ ²Mating Behavior Drives Seed Dispersal by the Long-wattled Umbrellabird Cephalopterus penduliger, Jordan Karubian, Renata Duraes, Jenny L. Storey, and Thomas B. Smith, BIOTROPICA 44(5): 689–698 2012