Jewish Book Week

I stopped by the Jewish Book Week on the way home. It’s the first day, so I’m still comparing prices and looking at titles and haven’t bought anything yet. One title really made my mind boggle: חכמי טרנסילבניה, The Sages of Transylvania. I wonder what they were studying. I didn’t open it, because I thought it would be an anti-climax, but wouldn’t it be great if there was a section on ולד הטומאה?