1933 GILDER MAIL / p.stat card "Robert Kronfeld Vier-länder-flug" to Czechoslovakia, uprated with airmail stamps., CDS WIEN 1/ 9.VII.33, violet flight cachet POST SEGELFLUG / ÖSTERREICH-UNGARN-ITALIEN-SCHWEIZ WIEN 1/ JULI 1933, on reverse arrival VIMPERK 1/ 20.VII.33; very fine