There seems to have been an international standard established for tickets to museums, such as the Byzantine Monuments of Thessaloniki. Each issues a ticket about the size of a bank note. The ticket has a larger portion with a photo of the museum or of an artifact from it. There are then perforated sections at either end, which are torn off and retained by the attendant at the door. Museum complexes may have multiple tear off sections (one had five) for different exhibits.
The tickets have some of the anti forgery features found on a bank note. All the tickets have micro printing in multiple colors as a backing to the ticket to make them difficult to photocopy or reproduce on a laser printer. The more expensive and popular museums have holographic strips and watermarks.
The tickets could make good souvenirs of a trip, when all placed in a frame together. However, one omission is that many do not say exactly where they are. After some weeks of traveling, you can forget which museum is where. For example, where are the Byzantine Monuments? The ticket has an image of gold and enamel bracelets from the White Tower, Thessaloniki, but where is the museum they are in?