Madsen, J., Tucker, G. M. (red.), Heath, M. F. (red.), Tomialojc, L. (red.) & Grimmett, R. F. A. (red.) (1994). Brent Goose (Branta bernicla). I Birdlife Conservation Series (s. 114-115). Birdlife International.
Fox, A. D. (2005). Brent Geese. I M. Nuttall (red.), Encyclopedia of the Arctic, Volume 1: A-F Index (s. 276-277). Frank Cass Publishers.