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Millennium-scale sunspot number reconstruction: evidence for an unusually active sun since the 1940s

Ilya G Usoskin1, Sami K Solanki, Manfred Schüssler

  • 1Sodankylä Geophysical Observatory (Oulu unit), University of Oulu, FIN-90014 Oulu, Finland. Ilya.Usoskin@oulu.fi

Physical Review Letters
|December 20, 2003
PubMed

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