RFC 4288:Media Type Specifications and Registratio...
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2. Media Type Registration Preliminaries


   Registration of a new media type or types starts with the
   construction of a registration proposal.  Registration may occur
   within several different registration trees that have different
   requirements, as discussed below.  In general, a new registration
   proposal is circulated and reviewed in a fashion appropriate to the
   tree involved.  The media type is then registered if the proposal is
   acceptable.  The following sections describe the requirements and
   procedures used for each of the different registration trees.



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