BCP
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... IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
...
... Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. ...
... Rekhter, Y., Moskowitz, B., Karrenberg, D., G. de Groot, and E. Lear, "Address Allocation for Private Internets", BCP 5, RFC 1918, February 1996. ...