diff --git a/Upload-Data.md b/Upload-Data.md
index 701a689..9a09a5c 100644
--- a/Upload-Data.md
+++ b/Upload-Data.md
@@ -2,6 +2,8 @@
 If the user wants to upload custom data (lutum/ec) they can use the FarmMaps file API.  
 The API is based on the google drive API.  
 
+C# explanation: https://developers.google.com/api-client-library/dotnet/guide/media_upload  
+
 * Start request
 
 > Request