I am interested in reading more about the social consensus theory. I looked up online, but found nothing more than the Wikipedia article.
Is there a book, or any kind of reference for this topic?
A good start would be Habermas' Theory of Communicative Action. It is very complex and hard to get into for a beginner and even advanced students without guidance, though. But I think every contempory theory regarding social concensus has to deal with the theoretical framework established and defended by Habermas.
For an introduction, see this Wikipedia entry