From Symbolics (Overview + Technical Summary):
http://bitsavers.informatik.uni-stuttgart.de/pdf/symbolics/h...
http://bitsavers.informatik.uni-stuttgart.de/pdf/symbolics/3...
Texas Instruments, Technical Summary
http://bitsavers.informatik.uni-stuttgart.de/pdf/ti/explorer...
Xerox Interlisp-D Friendly Primer
http://bitsavers.informatik.uni-stuttgart.de/pdf/xerox/inter...