Originally Posted by Nicholas

The receipt you are looking for is best obtained from any airpoprt agent. It's printed on actual ticket stock and shows the original booking class -- not upgrades -- so it doesn't matter when you request it during the one-year life of the ticket.

Receipts are usually sent by regular mail only when a ticket is reissued manually by DTWRR because of changes.

Also keep in mind that the automatic receipt you get by e-mail when you issue a ticket online doesn't contain a ticket number.