The passengers are identified on the basis of the ticket, so you have to present the ticket that enables you to participate. But we love trees, so the presentation by a smart device like phone or tablet is perfect.
However, IDs are not checked, only the number and type of the tickets. Therefore the first presenter of a valid ticket will be allowed to travel.
Cruising differently
Do I need to take the ticket for the trip? Are the tickets for a specific person?
