Trouble is that the author Miloslav Rechcígl (Czechized German surname) was a Czech (maybe), or came from Czech land (Bohemia) at least. Well, here's a picture of him :


He was a politician in the 1. Czecho-Slovak republic, then anti-nazi and emigrant to the US. He dealt with American Czech, Slovak and Jewish emigrants from Czecho-Slovakia. That's why he included Jews under Czech or Slovak term depending on where they came from. It's an American way of thinking, most probably… But we, Europeans, are able recognize a Jew quite easily. In my humble opinion Rechcígl was of Jewish origin too.

As Undead said, Goldberger and Weiss are Jewish surnames. Other Jewish surnames : Grossman, Newman, Bettelheim.

Most of Slavic surnames changed into some weird English forms in the US.

So, the article deals with American emigrants from Slovakia calling all of them Slovaks and that is absolutely not correct.