Jobling, J.A. (2010). "Otus". The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. p. 286. ISBN978-1-4081-2501-4.
Savigny, M.J.C. (1809). "Scops Ephialtes. Le petit duc". Description de l'Égypte, ou recueil des observations et des recherches qui ont été faites en Égypte. Vol. I. Paris: L'Imprimerie Impériale. p. 107.
Heaney, L. R. & Tabaranza, B. R. Jr. (2006). "Mammal and Land Bird Studies on Camiguin Island, Philippines: Background and Conservation Priorities". Fieldiana Zoology. New Series. 106: 1–13. doi:10.3158/0015-0754(2006)106[1:MALBSO]2.0.CO;2. S2CID129026301.
Heaney, L. R. & Tabaranza, B. R. Jr. (2006). "Mammal and Land Bird Studies on Camiguin Island, Philippines: Background and Conservation Priorities". Fieldiana Zoology. New Series. 106: 1–13. doi:10.3158/0015-0754(2006)106[1:MALBSO]2.0.CO;2. S2CID129026301.
Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (January 2021). "Owls". IOC World Bird List Version 11.1. International Ornithologists' Union. Retrieved 20 May 2021.