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. 2012 Aug 24;23:10.3402/mehd.v23i0.18958. doi: 10.3402/mehd.v23i0.18958

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© 2012 K.L. Reichelt et al.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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