Interesting 893 hits. I might have a look at Google's ngram viewer to get a sense of the frequency of use of these terms in books over time. The two terms have been in the education literature for some time but it may be helpful to look at the history of them. It seems student empowerment begins to appear in the 1990's but teacher authority as I might have guessed goes back into the 1920's. Does not help me.
The term democratic classroom appears as a term here.
A useful looking pickup: Close to the Heart: Teacher Authority in a Classroom Community
Ah, this is better. A good journal article that asks questions about words like authority and traces it back to Plato! Yay!
So into Google scholar and look for the cites. The paper was published in 2009. Only 4 but that's OK. Mentoring appears in one of the papers.
The authors don't have public Google scholar profiles but I can do Scholar searches for the authors if the paper looks more useful than I have imagined.
I think I need to go do some scribbling on paper, what the course calls mind mapping!