1. Auber, L (1941) The colours of feathers and their structural causes in varieties of the Budgerigar, Melopsittacus undulatus (Shaw). University of Edinburgh, Edinburgh, Scotland.
2. Bensch S, B Hansson, D Hasselquist & B Nielsen (2000) Partial albinism in a semi-isolated population of Great Reed Warblers. Hereditas 133: 167–170. https://doi.org/10.1111/j.1601-5223.2000.t01-1-00167.x
3. Bostwick, K (2016) Feathers and plumages. Pp. 63-99 in Lovette, IJ & JW Fitzpatrick (eds). Handbook of bird biology. Wiley-Blackwell, USA.
4. Cantú-Guzmán, JC & ME Sánchez-Saldaña (2018) Guía de identificación de Psitácidos mexicanos. Defenders of Wildlife, Teyeliz, México.
5. Collar, NJ, LP George, N Krabbe, NA Madroño, LG Naranjo, TA Parker & DC Wege (2000) Threatened birds of the Americas. BirdLife International, Cambridge, USA.