Challenges and Advantages of Modular Documentation 
Using a modular process has proven highly effective in developing both on-line and printed documentation. This paper identifies module types and structures, discusses technical, psychological, and management hurdles, and demonstrates how this process can improve consistency and quality. In addition it discusses tools and resources, preliminary planning, preparation of personnel, and (briefly) tracking results.
Greene, Linda L. STC Proceedings (2000). Articles>Documentation>Single Sourcing