BirdLife International (2012) The BirdLife checklist of the birds of the world, with conservation status and taxonomic sources. Version 5. Downloaded from http://www.birdlife.info/im/species/checklist.zip [.xls zipped 1 MB].
HBW and BirdLife International (2024). Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 8.1. Available at: https://datazone.birdlife.org/species/taxonomy retrieved August 26, 2024
Jones, A. W. (2020). Spectacled Tyrannulet (Zimmerius improbus), version 1.0. In Birds of the World (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.paltyr4.01 retrieved November 8, 2024
Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, G. Del-Rio, A. Jaramillo, D. F. Lane, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 28 September 2024. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved September 29, 2024
Gill, Frank; Donsker, David, eds. (2017). "Tyrant flycatchers". World Bird List Version 7.3. International Ornithologists' Union. Retrieved 9 January 2018.