... effect

Figures 10-12 are only available in electronic form at http://www.edpsciences.org

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... ODE

http://www.nordita.dk/software/pencil-code

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... paper

This forcing function was also used by Brandenburg (2001), but in his Eq. (5) the factor 2 in the denominator should have been replaced by $\sqrt{2}$ for a proper normalization.

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