Who wrote A Summer Place, the book on which the 1959 movie is based?

Sloan Wilson, author of The Man in the Gray Flannel Suit, wrote A Summer Place.

On what work was Dr. Strangelove (1964) based? Dr. Strangelove was based on a novel, Red Alert, by Peter George.
On what book was A Place in the Sun (1951) based? A Place in the Sun is based on the book An American Tragedy, by Theodore Dreiser.
Who played Flipper in the movie Flipper (1963)? Mitzi played Flipper. Susie played the dolphin in the sequel, Flipper's New Adventure (1964), and in the TV series "Flipper" (NBC, 1964-68).
How long has Charles Kuralt’s “On the Road” feature appeared on “The CBS Evening News”? Charles Kuralt's "On the Road" feature has appeared on "The CBS Evening News" since October 1967.
Whom did author Margaret Mitchell suggest to MGM to play Rhett Butler in Gone With the Wind (1939)? Groucho Marx was suggested to MGM to play Rhett Butler in Gone With the Wind, but only in jest.
On what book is The Heiress (1949) based? The Heiress is based on the book Washington Square, by Henry James.