diff --git a/contents/codes/418.md b/contents/codes/418.md
index 0f93d8f..938c04a 100644
--- a/contents/codes/418.md
+++ b/contents/codes/418.md
@@ -3,7 +3,6 @@ set: 4
 code: 418
 title: I'm a teapot
 references:
-    "Rails HTTP Status Symbol": ":i'm_a_teapot"
     "Go HTTP Status Constant": "http.StatusTeapot"
 ---