There was a time (not so long ago) where lecture notes were not published, not commonly at least, and their reproduction was expensive. In my case, that was precisely the time when the fields I'm most interested in (algebraic geometry & number theory) underwent an incredible and exciting period.
I think that many of the subtleties and most of the beauty of these days are actually found in the lecture notes who pioneered those dramatic changes. But most of these lecture notes might be lost in time by now.
I'd like to know if someone knows about a place where this kind of material could be found. I have some of these volumes (like Michael Artin's lecture notes on commutative rings, MIT 1966 or Nastold's lectures on homological algebra, Madrid mid-sixties). Despite the material is widely covered in many modern books, I always find gems (maybe a hidden remark, maybe an intuition) that still shine, after so many years.
Thanks for sharing.