diff --git a/README.md b/README.md
index b7b6d1a..c1d361a 100644
--- a/README.md
+++ b/README.md
@@ -80,3 +80,5 @@ Is the third version produced in the alpha phase.
 The digits of Pi will reset back to `3` when moving to a new phase.
 
 If the number gets too long, it will reset to one digit of 2π. Once that gets to long, it will be digits of 3π and etc.
+
+Named after [Psi](https://github.com/psi-im/psi).