LITTLE, I. T.; LITTLE, R. M. Cape Sparrows nesting in a Black-collared Barbet nest cavity. Biodiversity Observations, [S. l.], p. 41–43, 2015. DOI: 10.15641/bo.272. Disponível em: https://journals.uct.ac.za/index.php/BO/article/view/272. Acesso em: 11 nov. 2025.