1. Retired, 427 Homewood Circle, Frederick, MD 21702; formerly, Geodesist, NOAA’s National Geodetic Survey, 1315 East-West Highway, Silver Spring, MD 20190 (corresponding author). ORCID: .
2. Geodesist, NOAA’s National Geodetic Survey, 1315 East-West Highway, Silver Spring, MD 20190.
3. Geodesist, NOAA’s National Geodetic Survey, 1315 East-West Highway, Silver Spring, MD 20190. ORCID:
4. Professor, Dept. of Geoscience, Univ. of Wisconsin, A350 Weeks Hall, Madison, WI 53706.
5. Coordinator, Geological Survey of Colombia, Space Geodesy Research Group, Diagonal 53 No. 34-53, Bogotá 111321, Colombia.