I'm posting this just to capture knowledge that may have been lost or not fully appreciated. The URN specification defines a URN as being "urn:<NID>:<notation-specific-identifier>", where <NID> is the "notation ID". Notation IDs should be registered with the IANA and OASIS has registered the NID "oasis":
http://tools.ietf.org/html/rfc3121 If I had ever known about this I had forgotten it. I checked the URNs used in the grammars and they all follow the rules defined in RFC3121, so there's no action required. But I wanted to make sure all of us involved were aware of this requirement on URNs used for OASIS artifacts. Also, the spec should cite this RFC if it does not already since it's an OASIS-imposed rule and the DITA spec conforms to it. Cheers, E. ————— Eliot Kimber, Owner Contrext, LLC
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