Multiple dynamo modes as a mechanism for long-term solar activity variationsM. J. Käpylä, P. J. Käpylä, N. Olspert, A. Brandenburg, J. Warnecke, B. B. Karak and J. PeltA&A, 589 (2016) A56DOI: https://doi.org/10.1051/0004-6361/201527002
