I want to study FLT (Fermat's Last Theorem), and now I'm studying moduli of elliptic curves.

I've heard that Deligne-Rapoport, Katz-Mazur, Mazur's "Modular curves...", and Katz's "p-adic..." are very good for this topic.

But I don't know what's the difference between these papers. For me it seems that these treat almost same topics.

So what should I read at first? (Now I'm reading Katz-Mazur. It's easy to read even for me, a beginner of arithmetic geometry. So I think I should read it at first. And glancing through Mazur, it seems to use many results from other 3 papers.)

And would you recommend other good papers which I should understand for understanding FLT?

Any help will be much appreciated!