Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: Incredulous

Ken Timmerman wrote this book after reading Ms. Barbara Reynolds's book (search for "On March 12, 2002, Rob Redding interviewed Barbara Reynolds"), "Jesse Jackson: The Man, The Movement, and The Myth." So I'm very incredulous about this man's motivation and source material. Moreover, he has a degree in creative writing so I would not be surprised if his book is nothing but a creative derivation of Ms. Reynolds's book. Nevertheless, I refuse to buy it. However, I will read it if I'm able to obtain it for free (e.g. library).