An Ohio University spokesperson has confirmed that author Daniel Keyes has died at age 86.
The OU English professor emeritus is best known for his books "Flowers of Algernon" and "The Minds of Billy Milligan."
His story "Flowers of Algernon" started as a short story and was then expanded to a novel.
It was made into a movie, Charly, in 1968. Cliff Robertson won an Academy Award for his lead performance.
"The Minds Of Billy Milligan" was based on a series of interviews Keyes had with Milligan, who used multiple personality disorder as an insanity plea.
WOUB reported that Keyes died of pneumonia at his home in South Florida.