Hedges, S., Kumar, N.S., Nishant, M.S. & Karanth, K.U. (2012) Estimating density and abundance of elephants from sightings along line transects: field methods. Monitoring Elephant Populations and Assessing Threats: A Manual for Researchers, Managers and Conservationists (ed S. Hedges), pp. 151–161. Universities Press (India) Private Limited, Hyderabad, India.