Dhufar 1974 Cats 15b (French Birnan) set of 5 imperf progressive colour proofs comprising 3 individual colours (red, blue & yellow) plus 3 and all 4-colour composites unmounted mint
Dhufar 1974 Cats 15b (French Birnan) set of 5 imperf progressive colour proofs comprising 3 individual colours (red, blue & yellow) plus 3 and all 4-colour composites unmounted mint