[1] RFC 5988 - Web Linking ( (3/22/2012, 12:19:11 AM 版)) <http://tools.ietf.org/html/rfc5988#page-16>
[2] RFC 5829 - Link Relation Types for Simple Version Navigation between Web Resources (11/2/2014, 5:41:04 AM 版) <http://tools.ietf.org/html/rfc5829#section-4.4>
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