Results of a phylogeographic analysis evinces that the Caspian and Siberian tiger populations shared a common continuous geographic distribution until the early 19th century.[5]
Some Caspian tigers were intermediate in size between Siberian and Bengal tigers.[3][6][7]
^ abNowell, K. & Jackson, P. (1996). "Tiger, Panthera tigris (Linnaeus, 1758)"(PDF). Wild Cats: status survey and conservation action plan. Gland, Switzerland: IUCN/SSC Cat Specialist Group. pp. 55–65.
^Kitchener, A. C.; Breitenmoser-Würsten, C.; Eizirik, E.; Gentry, A.; Werdelin, L.; Wilting, A.; Yamaguchi, N.; Abramov, A. V.; Christiansen, P.; Driscoll, C.; Duckworth, J. W.; Johnson, W.; Luo, S.-J.; Meijaard, E.; O'Donoghue, P.; Sanderson, J.; Seymour, K.; Bruford, M.; Groves, C.; Hoffmann, M.; Nowell, K.; Timmons, Z. & Tobe, S. (2017). "A revised taxonomy of the Felidae: The final report of the Cat Classification Task Force of the IUCN Cat Specialist Group"(PDF). Cat News (Special Issue 11): 66–68.
^ abHeptner, V. G. & Sludskij, A. A. (1992) [1972]. "Tiger". Mlekopitajuščie Sovetskogo Soiuza. Moskva: Vysšaia Škola [Mammals of the Soviet Union. Volume II, Part 2. Carnivora (Hyaenas and Cats)]. Washington DC: Smithsonian Institution and the National Science Foundation. pp. 95–202.
^Firouz, E. (2005). "Tiger". The complete fauna of Iran. London, New York: I. B. Tauris. pp. 66–67. ISBN978-1-85043-946-2.
^Humphreys, P. & Kahrom, E. (1999). "Caspian tiger". Lion and Gazelle: The Mammals and Birds of Iran. Avon: Images Publishing. pp. 75–77. ISBN9781860642296.