Sunspot number recalibration: The ~1840–1920 anomaly in the observer normalization factors of the group sunspot number | Journal of Space Weather and Space Climate

Open Access

Issue		J. Space Weather Space Clim. Volume 7, 2017


Article Number		A12
Number of page(s)		11
DOI		https://doi.org/10.1051/swsc/2017010
Published online		05 May 2017

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