Refunds - Payment Request Invoices

Hi ,

We are going to do the refunds for the customers through AP.

So what the refund is finalised in AR, an invoice is created for the customer in payables, with the type of payment request.

One requirement of the client is to email the remittance advices to customers...However we are not clear from where the send separate remittance advice program is picking the email address of the customer.

Can someone please provide me the details?

Thanks and Regards,