Subject: Principal Triangulation of the North-East Quadrilateral; including The Gurwani Meridional; The Gora Meridional; The Hurilaong Meridional; The Chendwar Meridional; The North Parasnath Meridional; The North Maluncha Meridional; The Calcutta Meridional; The East Calcutta Longitudinal; The Brahmaputra Meridional; The Eastern Frontier Sec. 23à à ° to 26à à °; The Assam Longitudinal
Publisher: Office of the Trigonometrical Branch, Survey of India
Subject: Synopsis of the Results of the Operations of The Great Trigonometrical Survey of India; Descriptions and Co-ordinates of the Principal and Secondary Stations and Other Fixed Points of The Great Arc-Section 24à à ° to 30à à ° or Series A of the North-West Quadrilateral.
Publisher: Printed at the Office of the Great Trigonometrical Survey of India
Subject: Descriptions and Co-ordinates of the Principal and Secondary Stations and Other Fixed Points of The Rahun Meridional Series or Series E of the North-West Quadrilateral
Publisher: Printed at The Office of the Great Trigonometrical Survey of India, M. J. O'Connor
Subject: Descriptions and Co-ordinates of the Principal and Secondary Stations and Other Fixed Points of the Great Indus Series or Series D of the North-West Quadrilateral.
Publisher: Printed at the Office of the Great Trigonometrical Survey of India, M. J. O'Connor
Subject: Descriptions and coordinates of the principal and secondary stations and other fixed points of the Karachi Longitudinal Series or Series B of the North-West Quadrilateral
Publisher: Office of the Great Trigonometrical Survey of India