Mogul, J. and J. Postel, "Internet Standard Subnetting Procedure", STD 5, RFC 950, August 1985. 

Deering, S., "Host extensions for IP multicasting", STD 5, RFC 1112, August 1989.

Mogul, J., "Broadcasting Internet Datagrams", STD 5, RFC 919, October 1984.

Mogul, J., "Broadcasting Internet datagrams in the presence of subnets", STD 5, RFC 922, October 1984.

Postel, J., "Internet Protocol", STD 5, RFC 791, September 1981.

Postel, J., "Internet Control Message Protocol", STD 5, RFC 792, September 1981.

<https://www.rfc-editor.org/info/std5>