Bidspirit auction | Worldwide Air Post Stamps and
Worldwide Air Post Stamps and Postal History - Poland - 1954, 3rd Congress of Polish Philatelists, imperforate souvenir sheet of 5zl dark blue, full OG, NH, VF, C.v. $275, Scott #C34 footnote
Worldwide Air Post Stamps and Postal History - Poland - 1954, 3rd Congress of Polish Philatelists, imperforate souvenir sheet of 5zl dark blue, full OG, NH, VF, C.v. $275, Scott #C34 footnote