The most helpful book to learn XLISP I found 'Common Lisp, A Gentle Introduction to Symbolic Computation' by David Touretzky, mentioned in the Nyquist manual by Roger Dannenberg. The book can be downloaded for free from:
It's a book about Lisp in general, not only about Common Lisp, explaining and helping a lot to understand the the fundamental principles of Lisp programming.
Unfortunately there seems to be no specific information source about XLISP programming in the internet [beside the David Betz manual and the Tim I Mikkelsen documents], probably because most Lisp dialects have been merged into the Common Lisp standard in the 1980s and 1990s.
As a result of this I first had to learn Common Lisp to be able to re-construct how the examples in all the books could work with XLISP. This was a quite tedious way to learn and the main reason to start this document collection.
The official XLISP homepage is:
The official Nyquist homepage is:
Copies of 'Common Lisp, the Language,
It is a quite huge book explaining all details and discussions about the Common Lisp standard and is a real good Common Lisp information source. Unfortunately it is not very useful for learning XLISP out of it.
The most recent document about the Common Lisp standard is the 'Common Lisp Hypespec' [re-worked in 2005]. It is available for online reading under:
or as a 'tar.gz' package for offline reading from:
If you have no idea how to deal with 'tar.gz' packages on Windows computers and the 'tar.gz' file doesn't open automatically by clicking on it, the probably most easiest way is using the '7-zip' program available for free from: