> For functional programming specifically, you might try Simon
> Peyton-Jones's book "The Implementation of Functional Programming
> Languages".  This used to be available free here, but as I write the
> website is down:
> 
> http://research.microsoft.com/en-us/um/people/simonpj/papers/slpj-book-1987/

It works right now, and seams interresting indeed.
Thank you for this valuable bookmark.
I hope they use the same designations as in OCaml source for the more
abstract concept :)

> Best way to find out how OCaml is implemented is to read
> the source.

Yes, I'm doing plenty of that now.