TY  - RPRT
TI  - When did the average cosmic ray flux increase?
AU  - Nishiizumi, K.
AU  - Murty, S. V. S.
AU  - Marti, K.
AU  - Arnold, J. R.
PY  - 1985
UR  - https://ntrs.nasa.gov/citations/19850026784
ID  - 19850026784
ER  -