/**
* Adds a credit note to an invoice
*
* @param Invoice $invoice
* @return int
*/
public function invoicesAddCreditnote(Creditnote $creditnote)
{
$fields = $creditnote->toArrayForApi();
$id = $this->doCall('addCreditnote.php', $fields);
$creditnote->setId($id);
return $id;
}
