New research finds children understand the emotional benefits of following the rules / Medical News Today, 18 May 2005

http://www.medicalnewstoday.com/medicalnews.php?newsid=24590

When you shouldn't do what you want to do: Young children's
rules, and emotions by Lagattuta KH
PDF - http://www.ingentaconnect.com/content/bpl/cdev/2005/00000076/00000003/art00012