Fox, A. D., Ebbinge, B. S., Mitchell, C., Heinicke, T., Aarvak, T., Colhoun, K.
, Clausen, P., Dereliev, S., Faragó, S., Koffijberg, K., Kruckenberg, H., Loonen, M., Madsen, J., Mooij, J., Musil, P., Nilsson, L., Pihl, S. & van der Jeugd, H. (2010).
Current estimates of goose population sizes in the Western Palearctic, a gap analysis and assessment of trends.
Ornis Svecica,
20(3-4), 115-127.
Fox, A. D., Jónsson, J. E., Aarvak, T.
, Bregnballe, T., Christensen, T. K., Clausen, K. K., Clausen, P., Dalby, L., Holm, T. E., Pavón-Jordán, D.
, Laursen, K., Lehikoinen, A., Svein-Håkon, L., Møller, A. P., Nordström, M., Öst, M., Söderquist, P.
& Therkildsen, O. R. (2015).
Current and potential threats to Nordic duck populations – a horizon scanning exercise.
Annales Zoologici Fennici,
52(4), 193–220.
https://doi.org/10.5735/086.052.0404
Bregnballe, T., Carss, D. N., Lorentsen, S.-H., Newson, S., Pasquet, J.-Y., Parz-Gollner, R. & Volponi, S. (2013).
Counting cormorants. In D. N. Carss, R. Parz-Gollner & J. Trauttmansdorff (Eds.),
The INTERCAFE Field Manual: Research methods for Cormorants, fishes and the interactions between them (pp. 14-34). COST (European Cooperation in Science and Technology).
http://www.intercafeproject.net/COST.html