Vigne, L.; Martin, E.B. 2011.The ivory dynasty: A report on the soaring demand for elephant and mammoth ivory in southern China.London, Elephant Family, The Aspinall Foundation and Columbus Zoo and Aquarium.pp. 1-20.
PDF download available
Martin, E.B. 2010.From the jungle to Kathmandu: horn and tusk trade.Lalitpur, Wildlife Watch Group.pp. i-xi, 1-186.