fix(lang): remove ref to ISO 3166 (closes #488)

index.html

@@ -1387,16 +1387,14 @@ <h3>
           (see the <a href=
           "https://www.iana.org/assignments/language-subtag-registry">IANA
           Language Subtag Registry</a> for an authoritative list of possible
-          values, see also the <a href=
-          "https://www.iso.org/iso/country_codes/iso_3166_code_lists/country_names_and_code_elements">
-          Maintenance Agency for ISO 3166 country codes</a>). That is, a
-          language range is composed of one or more <dfn>subtags</dfn> that are
-          delimited by a U+002D HYPHEN-MINUS ("-"). For example, the
-          '<code>en-AU</code>' language range represents English as spoken in
-          Australia, and '<code>fr-CA</code>' represents French as spoken in
-          Canada. Language tags that meet the validity criteria of [[!RFC5646]]
-          section 2.2.9 that can be verified without reference to the IANA
-          Language Subtag Registry are considered structurally valid.
+          values). That is, a language range is composed of one or more
+          <dfn>subtags</dfn> that are delimited by a U+002D HYPHEN-MINUS ("-").
+          For example, the '<code>en-AU</code>' language range represents
+          English as spoken in Australia, and '<code>fr-CA</code>' represents
+          French as spoken in Canada. Language tags that meet the validity
+          criteria of [[!RFC5646]] section 2.2.9 that can be verified without
+          reference to the IANA Language Subtag Registry are considered
+          structurally valid.
         </p>
         <p>
           The <dfn>steps for processing the <code>lang</code> member</dfn> is