- Correspondence to Joana Paredes, IPATIMUP, Rua Dr Roberto Frias s/n, 4200-465 Porto, Portugal;
- Accepted May 22, 2011
- First published June 16, 2011.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.