References needed

[Paul L Schauble]

I'm looking for reference material on a couple of Unix topics. Stuff available
for ftp would do very well.

There is at least one book out on writing Unix device drivers. Is there one
recent enough to cover SVR4? Can someone give me title, author, and 
publisher(!)?

I also need medium level descriptions of operation for the Kerboros and NFS
protocols. Not the level of detail one would implement from, but rather
what you would use to teach someone about the architecture and function.

Pointers?

    Thanks in advance,
        ++PLS