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 /This paper released under the Apache License version 2.0; see [[file:./LICENSE.txt][LICENSE.txt]] for details./
 
+/For a broader overview of various anti-spam techniques, see [[https://github.com/WebOfTrustInfo/rwot9-prague/blob/master/topics-and-advance-readings/ap-unwanted-messages.md][AP Unwanted Messages]], which is in many ways informed this document but currently differs in some implementation rollout differs.  (These two documents may converge.) */
+
 * Conceptual overview
 
 ** ActivityPub