| number | text | implementations | |
| C058 | [S] | Specifications that define protocol or format elements (e.g. HTTP headers, XML attributes, etc.) which are to be interpreted as URI references (or specific subsets of URI references, such as absolute URI references, URIs, etc.) SHOULD use Internationalized Resource Identifiers (IRIs) [I-D IRI] (or an appropriate subset thereof). | SPARQL, SVG Tiny 1.2, XML Schema 1.1, XQuery |
| C059 | [S] | Specifications MUST define when the conversion from IRI references to URI references (or subsets thereof) takes place, in accordance with Internationalized Resource Identifiers (IRIs) [I-D IRI]. | XQuery, XLink 1.1 |
| C060 | [S] | Specifications that define new syntax for URIs, such as a new URI scheme or a new kind of fragment identifier, MUST specify that characters outside the US-ASCII repertoire are encoded using UTF-8 and %HH-escaping. | ??? |
| C061 | [S] | Specifications that define new syntax for URIs SHOULD also define the normalization requirements for the syntax they introduce. | XQuery |