TY - RPRT TI - Triangulation and primary traverse, 1916-1918. Primary traverse in Virginia, 1916-1918 AU - Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey PY - 1923 DO - 10.3133/b709l UR - https://pubs.usgs.gov/publication/b709L ID - b709L ER -