RFC 2308:Negative Caching of DNS Queries (DNS NCAC...
RFC-Ref

13. References

[RFC1034] Mockapetris, P., "DOMAIN NAMES - CONCEPTS AND FACILITIES," STD 13, RFC 1034std13, November 1987.
[RFC1035] Mockapetris, P., "DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION," STD 13, RFC 1035std13, November 1987.
[RFC2065] Eastlake, D., and C. Kaufman, "Domain Name System Security Extensions," RFC 2065(-> 2535(-> 4035prop | 4034prop | 4033prop)), January 1997.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels," BCP 14, RFC 2119, March 1997.
[RFC2181] Elz, R., and R. Bush, "Clarifications to the DNS Specification," RFC 2181prop, July 1997.

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