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@@ -422,7 +422,7 @@ This category is for any code project related to the Fediverse. They need not be
 
 ### Protocol specifications
 
-* [**ActivityPub Ontology**](https://github.com/steve-bate/activitypub-ontology): Turtle definitions of ActivityStreams 2.0 and Mastodon Toot vocabularies. `MIT, Turtle`
+* [**ActivityPub Ontology**](https://github.com/steve-bate/activitypub-ontology) ([site](https://www.stevebate.net/ontologies/activitystreams2)): Turtle definitions of ActivityStreams 2.0 and Mastodon Toot vocabularies. `MIT, Turtle`
 
 * :heavy_check_mark: [**LitePub**](https://github.com/litepub/litepub) ([Fedi account](https://pleroma.site/users/kaniini)): A set of extensions to AP, being developed by devs from Pleroma and Mastodon (status: for the most part litepub group folded back into SocialCG, see: [issue](https://github.com/litepub/litepub/issues/6))