(CBS News) Historians have long written about the possibility that Marilyn Monroe -- who died 51 years ago Monday -- and John F. Kennedy had a relationship.

Now, a new book claims Monroe actually called first lady Jacqueline Kennedy to talk about it.

The long rumored love affair between President John F. Kennedy and Marilyn Monroe is at the center of Christopher Andersen's new book, "These Few Precious Days: The Final Year of Jack with Jackie."

Presidential historian Doug Wead thinks Andersen's sensational revelations could well be true. He said, "It's the sort of thing that's unbelievable but really happens in history. Some of these things we're uncovering right now will move from speculation to fact as time progresses."...