I'm wondering where the MIPS I-IV standards that are referenced everywhere are defined. I was able to actually find what seems to be the IV standard [1] but found no such thing for I-III. I didn't even find any bibliographic references to them. Did they only exist as printed books and nobody bothered to scan them? Or are they under copyright? Would be nice to have them accessible somewhere.
[1] http://www.cs.cmu.edu/afs/cs/academic/class/15740-f97/public/doc/mips-isa.pdf