Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Liberia - 1936 (February 28), First Flight pre-printed cover on line Monrovia - Harper (322 miles), franked by black surcharge 6c on 2c violet, the same day Harper postmark on front and reverse, VF, expertized by G. Buhler, C.v. $275 for used stamp off cover, Est. $200-$300, Sc. #C1