text: public virtual AddSourceIdentifierToSubscriptionResponse AddSourceIdentifierToSubscription(AddSourceIdentifierToSubscriptionRequest request){var options = new InvokeOptions();options.RequestMarshaller = AddSourceIdentifierToSubscriptionRequestMarshaller.Instance;options.ResponseUnmarshaller = AddSourceIdentifierToSubscriptionResponseUnmarshaller.Instance;return Invoke<AddSourceIdentifierToSubscriptionResponse>(request, options);}