I think I was able to separate most of it. You would have no use for a dictionary because that's for looking up word definitions, not WWII information. You would have no use for a music index or art index because you're looking for information on concentration camps, and there was no music or art there. There also is no use for a telephone directory because you can't call anyone that would be able to help you or use an old one, because nearly all number owners from that age have passed.
There is a chance that your teacher would also not accept an atlas or gazetteer because those are map-related, but you could use those to look at the location of concentration camps.