Count Number of invoices in oracle APPS

i want a query to display how many invoices are created using a particular interface for the last one month in AR module. we are not using any other module except ar,ap ,gl.All our invoices ar开发者_StackOverflow社区e generated through interface only.Please tell me the table which i can find all the invoices created in AR module using a particular Interface.

This sounds simple to me but I don't have a lot of AR experience.
select count(*) from AP_INVOICES_ALL where CREATION_DATE > SYSDATE - 30 and SOURCE = '&source' ;