Shonvar is an American spelling so what can it be in Poland.
Should it start with SZ ONWAR or SZOWAR or who knows what an English speaker heard.
http://igrek.amzp.pl/mapindex.php?cat=WIG100http://lazarus.elte.hu/hun/digkonyv/topo/3felmeres.htmYou have 3 locations to start with Dukla, Humenne and Budapest. That is what you have on the documents that you showed me. Laszlo's manifest might be the tie breaker.