DOCBOOK: DSSSL or XSL

Hello

I'm starting to write my master's thesis and I will probably need to
adjust the output to conform to the faculty's rules.

In such a situation wich of the formatting languages mentioned in the
title is best, i.e., wich is more easily adaptable?

Thanks
-- 
        Mario Filipe 
        
        http://neptuno.sc.uevora.pt/~mjnf