TY  - RPRT
TI  - IGRFGRID : a program for creation of a total magnetic field (International Geomagnetic Reference Field) grid representing the earth's main magnetic field, Part B - Source code
AU  - Ronald E. Sweeney
PY  - 1990
DO  - 10.3133/ofr9045b
UR  - https://pubs.usgs.gov/publication/ofr9045B
ID  - ofr9045B
ER  -