Selma SEILER, born 21.03.1910, at Kostolna pri Dunaji (?), now in the Czech Republic (?), within a region which before World War I. belonged to Hungary.
The town of Kostolna pri Dunaji is in Slovak Republic.
http://mapy.atlas.sk
Up to 1993 it was Czechoslovakia and since then Czech Republic and Slovak Republic.
The old 1910 Hungarian megye map:
http://lazarus.elte.hu/hun/maps/1910 click on Pozsony megye to find Egyhazfa, old name of Kostolna pri Dunaji. Locate Pozsony (now Bratislava) proceed North-East to Szencz (Senec)and South of it is Egyhazfa.