Find a little bug in case

daluntw · web-flow · commit b4030450942d · 2017-10-24T08:28:06.000+08:00
diff --git a/USAGE.md b/USAGE.md
@@ -389,7 +389,7 @@ print response.headers
 ```
 ## Retrieve an existing API Key
 
-**This endpoint allows you to retrieve a single api key.**
+**This endpoint allows you to retrieve a single API key.**
 
 If the API Key ID does not exist an HTTP 404 will be returned.
 
