EAD Document Type Definition (DTD) is a standard for encoding archival finding aids using Extensible Markup Language (XML). The standard is maintained in the Network Development and MARC Standards Office of the Library of Congress (LC) in partnership with the Society of American Archivists.
A file is considered to be an EAD document when its namespace is "urn:isbn:1-931666-22-9" or its public ID is "//DTD ead.dtd (Encoded Archival Description (EAD) Version 2002)//EN".
EAD documents use a Relax NG Schema located in ${frameworks}/ead/rng/ead.rng, where ${frameworks} is a subdirectory of the Oxygen install directory.
The default XML catalog is stored in ${frameworks}/ead/catalog.xml.