TY - RPRT TI - Triangulation and primary traverse, 1916-1918. Primary traverse in Michigan, 1916-1917 AU - Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey PY - 1923 DO - 10.3133/b709f UR - https://pubs.usgs.gov/publication/b709F ID - b709F ER -