Provisional compilation. Topographic map of Wallhallow region, Northern Territory. Relief shown by spot heights.; "Spot elevations have been determined with the aid of aneroid barometers. It is estimated that the average error of these elevations is likely to be in the vicinity +/- 30 feet and that errors greater than +/- 100 feet are unlikely".; "Air photography by R.A.A.F., Oct., 1947".; Blueline print.; Also available online http://nla.gov.au/nla.map-vn5718313
