1. Boar. In: World book encyclopedia, vol. 2. Chicago: Field Enterprises Inc.; 1956. p. 853.
2. Available from: http://www.britishwildboar.org.uk/profile.html.
3. Wild Boar. In: Encyclopedia of the animal world, vol. 21. London: Sydney Bay Books; 1972. 1948–49.
4. Boar. In: The New Encyclopedia Britannica micropaedia ready reference, vol. 2. Chicago: Encyclopedia Britannica Inc.; 1987. p. 306.
5. Bull horn injuries in rural areas;Rau;Indian J Surg,1982