NEW YORK -- A pair of recently discovered early stories by prize-winning science fiction author Octavia Butler will be coming out as an e-book in June.

Open Road Integrated Media, a digital publisher, announced Tuesday that "A Necessary Being" and "Childfinder" will be compiled in a single volume titled "Unexpected Stories" that will be released June 24. The book will include an introduction by Walter Mosley.

Butler's literary agent, Merrilee Heifetz, found the stories, written in the early 1970s, among the author's papers at the Huntington Library in San Marino, Calif.

Butler, who died in 2006 at age 58, was known for such books as "Bloodchild and Other Stories" and the novel "Parable of the Sower." She was inducted posthumously into the Science Fiction and Fantasy Hall of Fame in 2010.