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The Relative Umbral Area in Spot Groups as an Index of Cyclic Variation of Solar Activity
Bludova, N. G., Obridko, V. N., Badalyan, O. G.Volume:
289
Language:
english
Journal:
Solar Physics
DOI:
10.1007/s11207-013-0370-0
Date:
March, 2014
File:
PDF, 667 KB
english, 2014