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.
♦ ²Camelus dromedarius, Ilse U. Köhler-Rollefson, MAMMALIAN SPECIES No. 375, pp. 1-8 (1991)