James Cagney Autograph All autographs & signed ephemera presented here is from the Cordelia Platt autograph collection. Highly regarded in the autograph industry, Cordelia was the president of the UACC (United autograph collectors club) and a well known dealer for many years. She was official authenticator of Marilyn Monroe. American Antique Auctions is proud to present a slice of history with this collection presented without reserve; the majority of which has not been seen or available for over 20 years.