Resource at http://www2.csr.utexas.edu/
http://www2.csr.utexas.edu/grace/RL06_mascons.html

Resource at https://podaac-tools.jpl.nasa.gov/
https://podaac-tools.jpl.nasa.gov/drive/files/GeodeticsGravity/tellus/L3/mascon/RL06/JPL/v02