A brief outline of the von Neumann architecture for a self replicating system.

John von Neumann.

"John von Neumann: computing's cold warrior", by Nathan Myhrvold.

John von Neumann.

Von Neumann's Universal Constructor

A page discussing artificial self replication is available.

Chapter 5 of Advanced Automation for Space Missions has a discussion of many of von Neumann's ideas, along with a more general discussion of artificial self replication.