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Keywords from Image Description:
Balloon flight Przemysl . STERREICH Ballonpost Przemysl blaue Feldpostkarte Nr mit Grutext geschrieben violetter Ballonpost Przemysl und Zensuriert Transit felzmann de Austrian Post Office PDold PD Prisoner of war mail Siege of Przemyl Censored covers Feldpost World War Airmail covers Philatelic uploads by Wwcensor