TY  - BOOK
AU  - Hale, George Ellery,
AU  - Nicholson, Seth Barnes,
TI  - Magnetic observation of sunspots, 1971-1924
U1  - Q 523.74 HAL 
PY  - 1938///
CY  - Washington, D.C.
PB  - Carnegie institution of Washington
KW  - Sun-spots
N1  - Papers of the Mount Wilson observatory, vol.v, pt. 1-2
ER  -