Quote From pjlu:

There's a guy called Biddle who is a sociologist. He wrote a couple of books on role theory: however, they are a bit dated in term's of - well, I think my reference for the one of his I used was 1971. So of course you need more recent ones as well when you use him-as only an aspect of my thesis includes role-I could then flesh him out with snippets and journal articles from more recent educational researchers, such as Pajares on roles and beliefs( Pajares though really has a teacher focus). Biddle really does go into role though and was fantastic to assist with my definitions.