What is a good paper (or other kind of source) to cite when talking about video game types and genres?

I am in my final year of my undergraduate games development course and so for part of my final year project (which involved making a game of course) I have to do a written report which needs to include references as appropriate. In the past when I showed my supervisor some of what I had done one of the things he zeroed in on as being something that should be tagged with a reference to something is my declaration that the game is "turn-based", and also my mention of RPGs when talking about existing games with similar systems.

I've tried Googling around a bit, mostly on Google Scholar, but I've yet to find anything suitable. I'm just looking for some things giving a good outline/definition of what constitutes a "turn-based game" and similarly an RPG. As I mentioned in the title it doesn't necessarily have to be a paper, so long as it provides what I need.