. 2013 Dec 16;7:31. doi: 10.1186/1754-1611-7-31
Copyright © 2013 Gu and Catchmark; licensee BioMed Central Ltd.
This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.