<swap>
<swapStream>
<payerPartyReference href="party1"/>
<receiverPartyReference href="party2"/>
</swapStream>
<swapStream>
<payerPartyReference href="party2"/>
<receiverPartyReference href="party1"/>
</swapStream>
<additionalPayment>
<payerPartyReference href="party1"/>
<receiverPartyReference href="party2"/>
</additionalPayment>
</swap>