[STD66]    Internet Standard 66,
              <https://www.rfc-editor.org/info/std66>.
              At the time of writing, this STD comprises the following:

              Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <https://www.rfc-editor.org/info/rfc3986>.