TY  - BOOK
AU  - Bartels, Julius
TI  - Collection of geomagnetic planetary indices Kp and derived daily indices, Ap and Cp, for the years 1932 to 1961
T2  - IAGA bulletin; no. 18
PY  - 1962///
CY  - Amsterdam
PB  - North-Holland
KW  - Geomagnetism
KW  - Geomagnetism - observations
ER  -