Tables for regional and local isostatic reduction (airy system) for gravity values T = 20 km, 30 km and 40 km, R = 0 km, 29,05 km, 58,10 km 116,20 km, 174,30 km and 232,40 km - Vening Meinesz, Felix A. 1887-1966 (Waltman, 1941)