Update functions-reference-csharp.md

Author: mhoeger

articles/azure-functions/functions-reference-csharp.md

@@ -352,9 +352,18 @@ The following assemblies are automatically added by the Azure Functions hosting
 
 The following assemblies may be referenced by simple-name (for example, `#r "AssemblyName"`):
 
+Functions V2 and V3:
 * `Newtonsoft.Json`
 * `Microsoft.WindowsAzure.Storage`
 
+Functions V1:
+* `Newtonsoft.Json`
+* `Microsoft.WindowsAzure.Storage`
+* `Microsoft.ServiceBus`
+* `Microsoft.AspNet.WebHooks.Receivers`
+* `Microsoft.AspNet.WebHooks.Common`
+* `Microsoft.Azure.NotificationHubs`
+
 ## Referencing custom assemblies
 
 To reference a custom assembly, you can use either a *shared* assembly or a *private* assembly: