TY  - RPRT
TI  - The magnetic field of the earth— 1985: Vertical intensity chart
AU  - N.W. Peddie
AU  - A.K. Zunde
PY  - 1988
DO  - 10.3133/gp987z
UR  - https://pubs.usgs.gov/publication/gp987Z
ID  - gp987Z
ER  -