Find out the smartform and driver program of a output type

Finding the smartform/sapscript name and driver program of a output type is fairly easy. Just go to NACE transaction and select the application. : Ex: for billing (VF01/02/03 its Billing) and click Output types button at the top.
Then Select the required output type and click ‘Processing Routines’ at the left hand side bar.
That's it :) . The processing routine will give you the driver program and smartform/form will give you the smartform/SAP script name.