diff --git a/examples/elm-spa-dev/public/content/guide/authentication.md b/examples/elm-spa-dev/public/content/guide/authentication.md
index a58f276..7b9a77a 100644
--- a/examples/elm-spa-dev/public/content/guide/authentication.md
+++ b/examples/elm-spa-dev/public/content/guide/authentication.md
@@ -21,7 +21,7 @@ If your app involves user authentication, you could make a `protectedSandbox` pa
 
 protectedSandbox :
   { init : User -> Url params -> model
-  , update : Msg -> model -> model
+  , update : msg -> model -> model
   , view : model -> Document msg
   }
   -> Page params (Maybe model) msg
@@ -74,4 +74,4 @@ But now you know that these functions will only be called if the `User` is reall
 
 ---
 
-That's it! Swing by the [`#elm-spa-users`](https://elmlang.herokuapp.com/) channel and say hello!
\ No newline at end of file
+That's it! Swing by the [`#elm-spa-users`](https://elmlang.herokuapp.com/) channel and say hello!