"SD012 Radom". birdlife.org. Retrieved 6 August 2011.
books.google.com
East, Rod; International Union for Conservation of Nature and Natural Resources. Antelope Specialist Group (1 June 1999). African antelope database 1998. IUCN. pp. 65, 175–. ISBN978-2-8317-0477-7. Retrieved 6 August 2011.