TY  - JOUR
T1  - On the Nature of Sun-Spots
JF  - Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character (1905-1934)
VL  - 95
IS  - 668
SP  - 234
EP  - 236
PY  - 1919/01/01/
UR  - http://dx.doi.org/10.1098/rspa.1919.0004
M3  - doi:10.1098/rspa.1919.0004
AU  - Hale, G.
ER  -