TY  - RPRT
TI  - Analysis of geomagnetic secular variation during 1980-1985 and 1985- 1990, and geomagnetic models proposed for the 1991 revision of the International Geomagnetic Reference Field
AU  - N.W. Peddie
PY  - 1992
DO  - 10.5636/jgg.44.735
UR  - https://pubs.usgs.gov/publication/70016829
ID  - 70016829
ER  -