C.A.R. Hoare's book Communicating Sequential Processes (CSP) should be useful. Also, Russ Cox (the principal author of the C code this library is based upon) has a brief history of this approach to threading, which might be informative.
CSP is a translation by Roger Peppe of Plan 9's libthread/channel.c. There are at least two forks that add new features, such as different queue choices, timeouts, and
ALT guard conditions: Calispel and ChanL.
The package is layered on top of Bordeaux-Threads for portability. It has had at least rudimentary testing under SBCL, Lispworks, openMCL, ECL and Allegro. Documentation and a couple of examples are included with the package.