Related Clues:
- Possibly, one's required to enter state
- A winning one at the races, perhaps
- Authority to travel
- Succeeding in travelling by showing this?
- Just the thing for the traveller?
- Maybe single set of policies in US elections
- (Price) label
- Parking offence notice
- It's me, young Herbert the composer
- Entry permit
- Permit to travel
- Answer to six point endorsement
- Entry/travel permit
- Permission to enter Virgin Islands initially with it
- Without it, excursion could get annulled at the outset