diff --git a/Fediverse.md b/Fediverse.md
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 # Fediverse
-This document covers how to block spam using Caterpillar in web applications using the federation based on the ActivityPub protocol (referred to as Fediverse), such as Mastodon, Misskey, Pleroma.
+This document covers how to block spam using Caterpillar Proxy in web applications using the federation based on the ActivityPub protocol (referred to as Fediverse), such as Mastodon, Misskey, Pleroma. [#](https://qiita.com/gnh1201/items/09f4081f84610db3a9d3)
 
 ## Spam filtering strategies
 * [K-Anonymity](https://en.wikipedia.org/wiki/K-anonymity) test - Estimating whether the characters has been arranged by humans. (use [Have I Been Pwned](https://haveibeenpwned.com/Passwords))