Thanks for this link, Nitro. From the look at my shelf, I could even add:
11/89 1352.00 Preliminary System Reference Manual
(consists of at least these volumes: Concepts, Reference, Appendices, all sharing the same number.)
5/89 NeXT on Campus (Spring 1989, Volume 1, Issue 1) (?, referenced in fall 90 edition, but I don't have it)
9/90 NeXT on Campus (Fall 1990, Volume 2, Issue 1)
1/91 NeXT on Campus (Winter 1991, Volume 2, Issue 2)
4/91 NeXT on Campus (Spring 1991, Volume 2, Issue 3)
10/91 NeXT on Campus (Fall 1991, Volume 3, Issue 1)
What interests me (besides filling the gaps in my collection) is also the question, what system was used at NeXT to write and produce their technical documentation.
To me, it looks as if FrameMaker had been used. Does anybody know more, are there any sources at all anywhere?