NGSのツール National Geodetic Survey National Geodetic Survey Geodetic Distance Conversions http://www.ngs.noaa.gov/TOOLS/Inv_Fwd/Inv_Fwd.html National Geodetic Survey http://www.ngs.noaa.gov/TOOLS/Inv_Fwd/Inv_Fwd.html National Geodetic Survey Online and downloadable PC-executable calculation utilities National Geodetic Survey Geo Inverse/Forward http://www.ngs.noaa.gov/TOOLS/Inv_Fwd/Inv_Fwd.html Geodetic azimuth and ellipsoidal distance National Geodetic Survey NGS online utility http://www.ngs.noaa.gov/TOOLS/Inv_Fwd/Inv_Fwd.html Geodetic Tool Kit