DULUTH, MN (KDAL) - Best selling Minnesota author John Sandford will be speaking and signing copies of his new book "Mad River" at the Barnes and Noble book store in the Miller Hill Mall on Wednesday.  "Mad River" is the latest installment of the popular series of suspense novels featuring Virgil Flowers, an investigator for the Minnesota Bureau of Criminal Aprehension.  John Sandford is the pseudonym for John Camp, a former reporter for the St. Paul Pioneer Press and the winner of two Pulitzer Prizes.  He will appear at Barnes and Noble with "Garage Logic" host Joe Soucheray at 7 p-m Wednesday to talk about the book and to sign copies.