The standards of measure and the base-lines : also an introductory account of the early operations of the Survey during the period 1800-1830 /
Walker, James Thomas,1826-1896.
India.Great Trigonometrical Survey.
Dehra Doon : Office of the Great Trigonometrical Survey,
1870.
India. Great Trigonometrical Survey.
Geodesy
Geodesy
Geodesy
Geodesy