Laura is the office manager of a doctor's office.Most office managers have authority to order medical supplies.Dr. Larry has given Laura authority to order medical equipment and supplies only after consulting with him.The salesman for the medical supply company came into the office asking for Dr. Larry.Dr. Larry told the salesman to speak to Laura about ordering medical supplies.The salesman offered Laura two tickets to the hottest show on Broadway if she orders over $5,000 in medical supplies todaywhich she does.Now Dr. Larry is furious since Laura did not have permission to place an order without his approval.He is refusing to pay for the medical supplies.What will the salesman use to support his claim of a valid order?