L<FS::cust_pay> - Payment class
+L<FS::cust_pay_void> - Voided payment class
+
L<FS::cust_bill_pay> - Payment application class
L<FS::cust_credit> - Credit class
L<FS::cust_refund> - Refund class
-L<FS::cust_credit_refund> - Refund application class
+L<FS::cust_credit_refund> - Refund application to credit class
+
+L<FS::cust_credit_bill> - Credit application to invoice class
-L<FS::cust_credit_bill> - Credit invoice application class
+L<FS::cust_pay_refund> - Refund application to payment class
L<FS::cust_pay_batch> - Credit card transaction queue class