Machado, Érika and Silveira, L.F. 2011.

Plumage variability and taxonomy of the Capped Seedeater Sporophila bouvreuil (Aves: Passeriformes: Emberizidae)

. Zootaxa. 2781, 1 (Mar. 2011), 49–62. DOI:https://doi.org/10.11646/zootaxa.2781.1.4.