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- http://www.incommon.org/metadata.html
- https://spaces.at.internet2.edu/display/InCCollaborate/Shibboleth+Metadata+Config
- https://spaces.at.internet2.edu/display/SHIB2/IdPMetadataProvider
- https://spaces.at.internet2.edu/display/SHIB2/NativeSPMetadataFilter
- https://spaces.at.internet2.edu/display/SHIB2/MetadataCorrectness