Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood (2018) The eBird/Clements checklist of birds of the world: Version 2018 http://www.birds.cornell.edu/clementschecklist/download, läst 2018-08-11
doi.org
Schulenberg, T. S. (2021). Violet-bellied Hummingbird (Chlorestes julie), version 1.1. In Birds of the World (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.vibhum1.01.1