Schulenberg, T. S. and C. W. Sedgwick (2020). Olivaceous Thornbill (Chalcostigma olivaceum), 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.olitho1.01 retrieved February 24, 2022