public PaymentRequest(string useragent, string description, string payerReference, string payeeReference, params Price[] prices)
        {
            UserAgent   = useragent;
            Description = description;
            if (prices != null)
            {
                Prices.AddRange(prices);
            }

            PayerReference           = payerReference;
            PayeeInfo.PayeeReference = payeeReference;
        }