AP Module - Understanding

Hi Guru's,

I am trying to understand the Process of Supplier Payments Goes on.

As i need to generate a present outstanding payment balance report for the Supplier  on  a particular Date.

So i was working with

F0411 - Supplier Ledger

F0413 - Accounts Payable - Matching Document

F0414 - Accounts Payable - Matching Document Detial.

But i am unable to get the logic of the table conenctivty and Balance. I got linked up

F0411 - Document linked to F0414 - Document

F0414 - PYID is linked to F0413 PYID.

My issue is to finding the balance payments....for a particular supplier on a partcular date.