When librarian Xu Zichen was sorting through donated books, he found a death notice tucked into "A Brief History of Time".
Three days later, the donor, Professor Sun, died of drug allergy and the police ruled it a suicide.
Xu Zichen found a second notice in another donated book, and the donor died in a car accident the next day.
When he investigated the third donor, a notice appeared in his mailbox.
"Xu Zichen will die within three days.
