The Darwin Information Typing Architecture (DITA) 1.2 specification defines a set of document types for authoring and organizing topic-oriented information, as well as a set of mechanisms for combining, extending, and constraining document types.

The DITA 1.2 Specification can be downloaded from:

http://docs.oasis-open.org/dita/v1.2/spec/DITA1.2-spec.html

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