In PaymentMeans there is an ASBIE called CardAccount. How do we differentiate whether it is a payer's or payee's CardAccount. In the case of FinancialAccount we differentiate via two ASBIEs, viz., PayerFinancialAccount and PayeeFinancialAccount. 

There is an associated issue in PaymentMeans/PaymentMandate which has PayerFinancialAccount but not a CardAccount - a prearranged payment under payment mandate can come out of a card account