1963, 40np Trucial States airmail cover to Switzerland, with corner card of Omanian Overseas Traders, franked with 40np reddish violet,
1963, 40np Trucial States airmail cover to Switzerland, with corner card of Omanian Overseas Traders, franked with 40np reddish violet, tied by Dubai double-circle, to St. Gallen, a deceptively elusive single-franking commercial usage, very fine.
