. 2009 Jan 5;7:1. doi: 10.1186/1546-0096-7-1
Copyright © 2009 Tofts et al; 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.
Figure 1.
Search strategy.