In one of the case studies in the textbook, Marcus Lane, a geologist for an environmental management and engineering services firm, traveled all over North and South America as part of his job, resulting in numerous expense reimbursements. Unfortunately, Lane went too far and began to double book his air travel using his personal credit card. He booked two separate flights to the same location, but with a huge cost difference. He used the cheaper ticket for the actual flight and returned the more expensive ticket for credit. And, of course, he submitted the more expensive ticket for reimbursement. How was his scheme detected?