Probably I'll try to backup all this and replace it with links to files later.
It's not easy to list all the nice books, or even to decide which books to list, but here are some.
Links to articles are dying surprisingly fast, I should fix them somehow.
It's useful to read about π-calculus (FAQ on π-Calculus) before reading about session types, and familiarity with typed λ-calculusis is assumed.
trx : Regular-tree expressions, now in Scheme:
Regular-tree expressions are to semi-structured data, such as XML and Lisp s-expressions, what standard regular expressions are to strings