Great book on how to structure your XML documents. Covers both XML and SGML. Tends to leans towards publishing oriented DTDs. Also contains a good section on Architectural Forms.

The closest anyone has come to putting rules of Structuring XML into pattern forms into a book. Tends to lean towards publishing oriented DTDs. An excellent resource.

Presents a process for developing SGML DTDs. Most of it can be applied to XML development as well. The best resource for a methodology for DTD development.

An excellent guide to XSLT. Includes a chapter with 4 XSLT Design Patterns.

Alexander introduces what patterns are all about and explains where their power comes from. Established a great foundation for building a pattern language. A must read for anyone serious about patterns.

A description of the pattern language that Alexander came up with for city planners and architects. Provides concrete examples of the power that patterns can provide.

The book that defined the patterns movement in the object-oriented development community. This work is often referred to as the "Gang of Four" (or GoF) book. A must read for Object-Oriented Software designers.

By one of the authors of the GoF book. Discusses the finer points and new insights of the patterns in the GoF book. Also discusses some of the process that went into writing the original book. Great for aspiring pattern authors in the object oriented software field.