1. Course textbook
Nancy A. Lynch, Distributed Algorithms. Morgan Kaufmann, 1996. ISBN 1558603484. QA76.9 D5 L963X 1996 (LC). Definitive textbook on formal analysis of distributed systems.
2. Other distributed computing textbooks
Hagit Attiya and Jennifer Welch, Distributed computing : fundamentals, simulations, and advanced topics, second edition. Wiley, 2004. QA76.9.D5 A75X 2004 (LC). ISBN 0-471-45324-2.
On-line version: http://dx.doi.org/10.1002/0471478210. (This may not work outside Yale.)
Errata: http://www.cs.technion.ac.il/~hagit/DC/2nd-errata.html.