United States: Postal History 1928, Graf Zeppelin Lakehurst to Friedrichshafen Flight, five co...

United States: Postal History
1928, Graf Zeppelin Lakehurst to Friedrichshafen Flight,
five covers, each with "First Flight Airmail / via Graf Zeppelin / United States - Germany / Oct 28 1928" violet confirmation cachet, four to Germany, one to Switzerland, a lovely array of multiple frankings, a few with light wrinkles or corner creases, attractive and chiefly fine. (Frost 127-7Aa, Sieger 22B)
Cover