Taxon - Odkazy a literatura
Gill F., Donsker D. & Rasmussen P. (eds): IOC World Bird List 11.1 [http://www.worldbirdnames.org/] [jako Strix aluco biddulphi (Scully, 1881)]Datum citace: 22. duben 2021
Clements, J. F.: eBird/Clements checklist of birds of the world 6.7, Cornell Lab of Ornithology [jako Strix aluco biddulphi]Datum citace: 25. duben 2013