Here's a link to an article in a linguistics journal that sounded interesting -- I have to still look at it!
"Problematizing the Dual in a Dual-Immersion Program: A Portrait"
"http://tc.liblink.umn.edu/sfx_local?sid=CSA:llba-set-c&pid=%3cAN%3e200208666%3c%2fAN%3e%26%3cAU%3eRubinstein%2dAvila%2c+Eliane%3c%2fAU%3e&issn=0898-5898&date=2002&volume=13&issue=1&epage=87&spage=65&genre=article&aulast=Rubinstein%2dAvila&aufirst=Eliane&title=Linguistics+and+Education&atitle=Problematizing+the+%22Dual%22+in+a+Dual%2dImmersion+Program%3a+A+Portrait">Problematizing the Dual in a Dual-Immersion Program: A Portrait
Author: Rubinstein-Avila Eliane E
From: Linguistics and education
Date: 2002
Volume: 13
Issue: 1
ISSN: 0898-5898
Pages: 65-87