You could also like to read some documents from Karl Bischoff (the architect of Auschwitz)

https://www.yadvashem.org/yv/en/exhibitions/through-the-lens...

And also Vrba–Wetzler report

https://en.wikipedia.org/wiki/Vrba–Wetzler_report

I don't want someone to think that i'm blaming someone for reading stuff. I just think and see that sometimes for people it is very easy to forget or miss bad things (harm to society) when their salary (or income) depends on ignoring this.