ISO/IEC 19757-03 Document Schema Definition Language (DSDL) -- Part 2: Regular-grammar-based validation -- RELAX NG.
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ISO/IEC 19757-08 Document Schema Definition Language (DSDL) -- Part 2: Regular-grammar-based validation -- RELAX NG. Article introducing RELAX NG using the compact syntax. Provides some information on how to implement a RELAX NG validator.
The second edition is created by consolidating the first edition and Amd06 and then fixing some bugs. XML and the IETF: Making the case for RELAX NG, Michael Smith, xmlhack. The rng-users mailing list is for anything related to the use of RELAX NG.
RELAX NG DTD Compatibility, OASIS Committee Specification, 3 December 2001. Reports on arguments advanced as to why RELAX NG is preferable to W3C XML Schema, in the context of IETF discussions on XML. Paper discussing the thinking behind the design of RELAX NG.
Defines annotations and datatypes that support some of the features from XML 1.0 DTDs not supported directly by RELAX NG. XML Matters: Kicking back with RELAX NG, Part 1, Part 2, Part 3, David Mertz, IBM developer Works.
Proof of concept implementation of the idea of embedding XML processing pipelines in a grammar.
Maneki Neko, Xerces parser configuration that supports RELAX NG validation.
Jericho HTML Parser is a java library allowing analysis and manipulation of parts of an HTML document, including server-side tags, while reproducing verbatim any unrecognised or invalid HTML.