1. Mockapetris, P.V.: Domain names-concepts and facilities. Internet Engineering Task Force, RFC1034 (1987). http://www.ietf.org/rfc/rfc1034.txt
2. Mockapetris, P.V.: Domain names-implementation and specification. Internet Engineering Task Force, RFC1035 (1987). http://www.ietf.org/rfc/rfc1035.txt
3. Elz, R., Bush, R., Bradner, S., Patton, M.: Selection and operation of secondary DNS servers. Internet Engineering Task Force, RFC2182 (1997). http://www.ietf.org/rfc/rfc2182.txt
4. Rosenbaum, R.: RFC 1464-using the domain name system to store arbitrary string attributes (1987). http://www.ietf.org/rfc/rfc1464.txt
5. Arends, R., Austein, R., Larson, M., Massey, D., Rose, S.: RFC 4033: DNS security introduction and requirements (2005). http://www.ietf.org/rfc/rfc4033.txt