1. IOR/V/19/226 Reference (shelfmark): IOR/V/19/226 Title: Survey of India Professional Paper No. 19, Experiments in aeroplane photo surveying. C.G. Lewis & H.G. Salmond. Dehra Dun, 1920 Collection Area: India Office Records and Private Papers Languages: English Date Range: 1920 Extent: 1 volume