public function setupOrderReference()
    {
        $orderTotal = new OffAmazonPaymentsService_Model_OrderTotal();
        $orderTotal->setCurrencyCode($this->_currencyCode);
        $orderTotal->setAmount($this->_orderTotalAmount);
        
        $setOrderReferenceDetailsRequest 
            = new OffAmazonPaymentsService_Model_SetOrderReferenceDetailsRequest();
        $setOrderReferenceDetailsRequest->setSellerId($this->_sellerId);
        $setOrderReferenceDetailsRequest
            ->setAmazonOrderReferenceId($this->_amazonOrderReferenceId);
        $setOrderReferenceDetailsRequest
            ->setOrderReferenceAttributes(
                new OffAmazonPaymentsService_Model_OrderReferenceAttributes()
            );
        $setOrderReferenceDetailsRequest
            ->getOrderReferenceAttributes()->setOrderTotal($orderTotal);
        
        return $this->_service->setOrderReferenceDetails(
            $setOrderReferenceDetailsRequest
        );
    }