[1] draft-mogul-http-dupsup-00 - Duplicate Suppression in HTTP (10/26/2014, 12:59:10 PM 版) <http://tools.ietf.org/html/draft-mogul-http-dupsup-00#section-5.2.2>
[2] RFC 4229 - HTTP Header Field Registrations (11/2/2014, 9:53:20 AM 版) <http://tools.ietf.org/html/rfc4229#section-2.2.10>
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