Literature

• Catalogue of Life. Species 2000 & ITIS. [link]

Literature references linked to higher taxa

• eBird: An online database of bird distribution and abundance. eBird, Ithaca, New York. [link] (Aves)
• Gill, F & D. Donsker (eds) 2017. IOC World Bird List v7.1. [link] (Apodidae)