[STD80]    Internet Standard 80,
              <https://www.rfc-editor.org/info/std80>.
              At the time of writing, this STD comprises the following:

              Cerf, V., "ASCII format for network interchange", STD 80,
              RFC 20, DOI 10.17487/RFC0020, October 1969,
              <https://www.rfc-editor.org/info/rfc20>.