diff --git a/pages/formula/[...slug].js b/pages/formula/[...slug].js
index 890e8a1..4f54a68 100644
--- a/pages/formula/[...slug].js
+++ b/pages/formula/[...slug].js
@@ -2,6 +2,11 @@ import { promises as fs } from 'fs'
 
 import Layout from '@/components/layout/default.js'
 
+// Based on
+// https://github.com/lfades/static-tweet/blob/b2a1044d881cca88e7761491d4f22c8908497d92/pages/t/%5Btweet%5D.js
+// https://github.com/lfades/static-tweet
+// https://github.com/chibicode/reactions/blob/master/pages/index.js
+
 function HomebrewFormula( props ) {
     // const {
     //     app