1. Ptichii gripp i drugie vidy zoonoznogo grippa [Avian influenza and other zoonotic influenza]. Available at: https://www.who.int/ru/news-room/fact-sheets/detail/influenza-(avian-and-otherzoonotic) (accessed 08.10.2018)
2. Ptichii gripp: otsenka ugrozy pandemii. Vsemirnaya organizatsiya zdravookhraneniya [Avian influenza: an assessment of the threat of a pandemic. World Health Organization]. 2005 Available at: https://apps.who.int/iris/bitstream/handle/10665/68985/WHO_CDS_2005.29_rus.pdf;jsessionid=EE02AFF8C2A44DAFB3066AC8D1AD335F?sequence=2 (accessed 08.10.2018)
3. Krivenko V.G., Vinogradov V.G. Sovremennoe sostoyanie resursov vodoplavayushchikh ptits Rossii i problemy ikh okhrany [The current state of the resources of waterfowl of Russia and the problems of their protection]. Moscow, 2003. (In Russian) Available at: http://biodat.ru/doc/ducks/ (accessed 08.10.2018)
4. Mikheev A.V. Vidimyi dnevnoi prolet vodnykh i okolovodnykh ptits po zapadnomu poberezh'yu Kaspiiskogo morya [Visible day flight of water and near-water birds along the western coast of the Caspian Sea]. Stavropol', 1997, 160 p. (In Russian)
5. Vilkov E.V. Ornitofauna of the lagoon complex of the Middle Caspian. In: Sbornik nauchnykh statei «Inventarizatsiya, monitoring i okhrana klyuchevykh ornitologicheskikh territorii Rossii» [Collection of scientific articles “Inventory, monitoring and protection of key ornithological territories of Russia”]. 1999, pp. 75-82. (In Russian)