diff --git a/fish/.config/fish/functions/__history_previous_command.fish b/fish/.config/fish/functions/__history_previous_command.fish
index 4055545..3327318 100755
--- a/fish/.config/fish/functions/__history_previous_command.fish
+++ b/fish/.config/fish/functions/__history_previous_command.fish
@@ -1,3 +1,4 @@
+# Source: https://github.com/oh-my-fish/plugin-bang-bang
 function __history_previous_command
   switch (commandline -t)
   case "!"
diff --git a/fish/.config/fish/functions/__history_previous_command_arguments.fish b/fish/.config/fish/functions/__history_previous_command_arguments.fish
index adc8fbd..d9427b3 100755
--- a/fish/.config/fish/functions/__history_previous_command_arguments.fish
+++ b/fish/.config/fish/functions/__history_previous_command_arguments.fish
@@ -1,3 +1,4 @@
+# Source: https://github.com/oh-my-fish/plugin-bang-bang
 function __history_previous_command_arguments
   switch (commandline -t)
   case "!"