Michel 227 M - Airmail stamp 4 crowns with "FLUGPOST" overprint vertically centred, verified, cancelled

Austrian stamp "Airmail stamp for the Vienna-Krakow-Lviv-Kiev route" 4 crowns from 1918, colour change of previous crown values with heavily shifted overprint ‘FLUGPOST’ vertically centred, intaglio printing, line perforation 12½, verified, cancelled