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^bChen et al. 2006;

^cGu et al. 2007;

^dApoil et al. 2007;

^eManco et al. 2006;

^fChen et al. 2008;

^gOkubo et al. 2007;

^hUdaka et al. 2007;

ⁱBouchet et al. 2007;

^jHayakawa et al. 2001;

^kOstertag and Kazazian 2001a;

^lMiné et al. 2007.