diff --git a/speak.sh b/speak.sh
index 022f780..9a10369 100755
--- a/speak.sh
+++ b/speak.sh
@@ -1,5 +1,6 @@
 #!/bin/bash
 # https://trac.ffmpeg.org/wiki/How%20to%20speed%20up%20/%20slow%20down%20a%20video
+# https://github.com/mozilla/TTS
 #
 
 if [ -z "$1" ]; then