TY  - GEN
AU  - Donald H Zacharisen
C2  - , National Institute of Standards and Technology, Gaithersburg, MD
DA  - 1959-01-01 05:01:00
DO  - https://doi.org/10.6028/NBS.TN.2
LA  - en
PB  - , National Institute of Standards and Technology, Gaithersburg, MD
PY  - 1959
TI  - World maps of F2 critical frequencies and maximum usable frequency factors:
ER  -