diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 6520d28b..74977046 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -24,7 +24,9 @@ Example entry:
 | [NASA](https://api.nasa.gov) | NASA data, including imagery | No | Yes | Yes |
 ```
 
-\* Currently, the only accepted inputs for the `Auth` field are as follows:
+The URL must start with `http://` or `https://`.
+
+Currently, the only accepted inputs for the `Auth` field are as follows:
 
 -   `OAuth` - _the API supports OAuth_
 -   `apiKey` - _the API uses a private key string/token for authentication - try and use the correct parameter_
@@ -32,7 +34,7 @@ Example entry:
 -   `No` - _the API requires no authentication to run_
 -   `User-Agent` - _the name of the header to be sent with requests to the API_
 
-\* Currently, the only accepted inputs for the `CORS` field are as follows:
+Currently, the only accepted inputs for the `CORS` field are as follows:
 
 -   `Yes` - _the API supports CORS_
 -   `No` - _the API does not support CORS_