K. K. Srivastava, V. J. Zacharias, A. K. Bhardwaj, P. Joseph, and S. Joseph, “Some Observations on Troop Structure, Activity Budget and Food Habits of the Nilgiri Langur (<I>Presbytis johnii</I>) in Periyar During Monsoon (June - August)”, Indian Forester, vol. 122, no. 10, pp. 946–950, Oct. 1996.