Rando, Juan Carlos, Josep Antoni Alcover, Storrs L. Olson, and Harald Pieper. 2013. “A New Species of Extinct Scops Owl (Aves: Strigiformes: Strigidae: Otus) from São Miguel Island (Azores Archipelago, North Atlantic Ocean)”. Zootaxa 3647 (2). Auckland, New Zealand:343–357. https://doi.org/10.11646/zootaxa.3647.2.6.