References

   [RFC1035]
      Mockapetris, P., "Domain Names - Implementation and
      Specification", STD 13, RFC 1035, USC/Information Sciences
      Institute, November 1987.

   [RFC1982]
      Elz, R., "Serial Number Arithmetic", RFC 1982, University of
      Melbourne, August 1996.

   [RFC1995]
      Ohta, M., "Incremental Zone Transfer", RFC 1995, Tokyo Institute
      of Technology, August 1996.

   [RFC1996]
      Vixie, P., "A Mechanism for Prompt Notification of Zone Changes",
      RFC 1996, Internet Software Consortium, August 1996.

   [RFC2065]
      Eastlake, D., and C. Kaufman, "Domain Name System Protocol
      Security Extensions", RFC 2065, January 1997.

   [RFC2137]
      Eastlake, D., "Secure Domain Name System Dynamic Update", RFC
      2137, April 1997.