diff --git a/readme.mdown b/readme.mdown
index 1dc47ae..7dbc4bf 100644
--- a/readme.mdown
+++ b/readme.mdown
@@ -29,6 +29,12 @@ The manual process for communicating blocked nodes to other nodes.
 A node should be able to subscribe to a larger node for their filters.
 With multiple subscriptions a node could look for a consensus among trust notaries.
 
+# activity pub references
+
+As far as I know, [domain-blocks] is as far as mastodon has gotten for inter-nodal moderation.
+[domain-blocks]: (https://source.joinmastodon.org/mastodon/docs/blob/master/content/en/api/rest/domain-blocks.md)
+I remember seeing a list posted by [@Gargron](https://mastodon.social/@Gargron) of domains that had media restrictions placed on them but I can't find any mention of this in mastodon's documentation.
+
 # design inspiration
 
 - [SSL And The Future Of Authenticity](https://www.youtube.com/watch?v=8N4sb-SEpcg)