The following bibliography has been generated by bringing together all references provided by our content partners. There may be duplication.


  • 1. National Biodiversity Network Species Dictionary (January, 2004) External link.
  • 2. Mullarney, K., Svensson, L., Zetterström, D. and Grant, P.J. (1999) Collins Bird Guide. HarperCollins Publishers Ltd, London.
  • 2006. website, Zoonomen - Zoological Nomenclature Resource, 2006.12.10
  • 3. RSPB A-Z of Birds: Bewick's swan (February, 2004) External link.
  • 4. JNCC Special Protection Areas for Bewick's swan (February, 2004) External link.
  • 5. Greenoak, F. (1979) All the birds of the air. Book Club Associates, London.
  • 6. Holden, P. and Sharrock, J.T.R. (2002) The RSPB Guide to British Birds. Pan Macmillan, London.
  • 7. Lack, P. (1986) The Atlas of wintering birds in Britain and Ireland. T & A D Poyser Ltd, London.
  • Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2014. The eBird/Clements checklist of birds of the world: Version 6.9. Downloaded from
  • Orrell T. (custodian) (2015). ITIS Global: The Integrated Taxonomic Information System (version Mar 2015). In: Species 2000 & ITIS Catalogue of Life, 26th August 2015 (Roskov Y., Abucay L., Orrell T., Nicolson D., Kunze T., Flann C., Bailly N., Kirk P., Bourgoin T., DeWalt R.E., Decock W., De Wever A., eds). Digital resource at Species 2000: Naturalis, Leiden, the Netherlands. ISSN 2405-8858.


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