After sparking ire with her controversial book The Rape of Nanking, Iris Chang apparently committed suicide at the age of 36, but some questioned whether the real cause of death was murder. Chang’s friend Paula Kamen searched for answers, investigating the author’s life (and death) in her new book Finding Iris Chang: Friendship, Ambition and an Extraordinary Mind. She’ll talk about what she unearthed tonight at the Schwartz Bookshop in Shorewood at 7 p.m.