public static function addRecurring($options = array())
    {
        $api = new Api\AddRecurring();

        if (isset($options['transactionId'])) {
            $api->setTransactionId($options['transactionId']);
        }
        if (isset($options['amount'])) {
            $amount = round($options['amount'] * 100);
            $api->setAmount(round($amount));
        }
        if (isset($options['description'])) {
            $api->setDescription($options['description']);
        }
        if (isset($options['extra1'])) {
            $api->setExtra1($options['extra1']);
        }
        if (isset($options['extra2'])) {
            $api->setExtra2($options['extra2']);
        }
        if (isset($options['extra3'])) {
            $api->setExtra3($options['extra3']);
        }
        $result = $api->doRequest();

        return new Result\AddRecurring($result);
    }