Spragens, K. A., Bjerre, E. R. and Black, J. M. (2013) “Black Brant Branta bernicla nigricans grit acquisition at Humboldt Bay, California, USA”, Wildfowl, pp. 104–115. Available at: https://tidsskrift.dk/Wildfowl/article/view/153609 (Accessed: 16 December 2025).