The main documentation reference for Common Lisp is, of course, the Common Lisp HyperSpec. For CMUCL, we have
- The CMUCL User's Manual, a detailed document containing information on the Python compiler and CMUCL extensions, in several formats:
- The CLX manual for online browsing or in gzipped tarred Postscript.
- The CMUCL Motif Toolkit:
- The design document describing the internals of CMUCL. This is very incomplete:
- Internal design of CMU common Lisp on the IBM RT PC, a nice introduction to the early design of CMUCL for the RT PC.
For some background on the CMUCL Project, see the History of the CMUCL Project.