--- a/doc/doap.xml	Wed May 12 01:11:42 2021 +0200
+++ b/doc/doap.xml	Sun May 16 16:52:59 2021 +0200
@@ -52,6 +52,7 @@
     <implements rdf:resource="https://www.rfc-editor.org/info/rfc6121"/>
     <implements rdf:resource="https://www.rfc-editor.org/info/rfc6122"/>
     <implements rdf:resource="https://www.rfc-editor.org/info/rfc6455"/>
+    <implements rdf:resource="https://www.rfc-editor.org/info/rfc7233"/>
     <implements rdf:resource="https://www.rfc-editor.org/info/rfc7301"/>
     <implements rdf:resource="https://www.rfc-editor.org/info/rfc7395"/>
     <implements rdf:resource="https://www.rfc-editor.org/info/rfc7590"/>