An Introduction to Programming with Threads
, by A. D. Birrell. I have better luck dealing with the PDF version than with the Postscript version.
POSIX Threads Programming
tutorial, at LLNL.
The Nachos Instructional Operating System
, by T. Anderson et al.
MIPS Architecture Documentation
Xen virtual machine
, developed at the University of Cambridge, England.
The Linux Kernel HOWTO
, by B. Ward.
What really happened on Mars?
, by M. Jones - an extra reason to study operating systems.