Lenox-conyngham, G. P. “Report on the Levelling Carried Out to Ascertain the Motion , If Any of Bench Marks Fixed to Trees in the Compound of the Trignometrical Survey Office, Dehra Dun, During the Period April 1914 to April 1917”. Indian Forester 43 (11-12):505-9. https://doi.org/10.36808/if/1917/v43i11-12/18182.