McGowan, Kevin J. (2020). "Fish Crow (Corvus ossifragus)". In Poole, A. F.; Gill, F. B. (eds.). Birds of the World. Ithaca, NY: Cornell Lab of Ornithology. doi:10.2173/bow.fiscro.01. Retrieved 12 December 2021.
McGowan, Kevin J. (2020). "Fish Crow (Corvus ossifragus)". In Poole, A. F.; Gill, F. B. (eds.). Birds of the World. Ithaca, NY: Cornell Lab of Ornithology. doi:10.2173/bow.fiscro.01. Retrieved 12 December 2021.