A book based on the recently closed international investigation into who betrayed Anne Frank to the Nazis has been called “downright ridiculous and reprehensible” by Holocaust historians in the Netherlands. Published this week, author Rosemary Sullivan’s “The Betrayal of Anne Frank: A Cold Case Investigation” follows investigators who used artificial intelligence to determine who betrayed the Jewish diarist’s so-called “secret annex,” where she and her family hid from the Nazis. Since Frank perished in 1945, numerous investigations, documentaries and books have attempted to solve that mystery.