The ESRI Guide to GIS Analysis Volume 1: Geographic Patterns & Relationships
"This is not a software manual, and it rightly avoids tying to any  particular brand or version of GIS. So although its origins are in ESRI, it should be valuable to users working with other brands of GIS, and will be useful to professionals who are concerned about interoperability across different brands, because of its focus on the basic principles of simple spatial analysis rather than on any one software product. ESRI has done the field a great service by sponsoring and publishing this book".  --Michael F. Goodchild National Center for Geographic Information and Analysis University of California, Santa Barbara