I encountered this term Hindley-Milner, and I\'m not sure if grasp what it means.
I\'ve read the following posts:
You may be able to find the original papers using Google Scholar or CiteSeer -- or your local university library. The first is old enough that you may have to find bound copies of the journal, I couldn't find it online. The link that I found for the other one was broken, but there might be others. You'll certainly be able to find papers that cite these.
Hindley, Roger J, The principal type scheme of an object in combinatory logic, Transactions of the American Mathematical Society, 1969.
Milner, Robin, A Theory of Type Polymorphism, Journal of Computer and System Sciences, 1978.