Concurrent Programming: Principles and Practice, by Gregory R. Andrews, Benjamin/Cummings Publishing Company, Inc., 1991.
For those interested in an advanced discussion of the principles and theory of concurrency.
Java Concurrency in Practice, by Brian Goetz, Tim Peierls, Joshua Bloch, Joseph Bowbeer, David Hulmes, Doug Lea, Addison-Wesley, 2006.
For those interested in advanced concurrency in Java.
Programming with POSIX Threads, by David R. Butenhof, Addison-Wesley, 1997.
For those interested in advanced concurrency in PThreads.
Concurrency in Ada, by Alan Burns and Andy Wellings, Cambridge University Press, 1998, 2nd Ed.
For those interested in advanced concurrency in Ada.