Books
Goodnight Moon by Margaret Wise Brown
The Tower Treasure (The Hardy Boys, #1) by Franklin W. Dixon
The House on the Cliff (The Hardy Boys, #2) by Franklin W. Dixon
The Secret of the Old Mill (The Hardy Boys, #3) by Franklin W. Dixon
The Bridge of San Luis Rey by Thornton Wilder
Men Without Women by Ernest Hemingway
Aspects of the Novel by E.M. Forester
The Colour Out of Space by H.P. Lovecraft
Twilight Sleep by Edith Wharton
Mosquitoes by William Faulkner
The Runaway Bunny by Margaret Wise Brown
Gentlemen Prefer Blondes / But Gentlemen Marry Brunettes by Anita Loos
Steppenwolf by Hermann Hesse
To the Lighthouse by Virginia Wolff
The Big Four by Agatha Christie
Amerika by Franz Kafka
The Gangs of New York by Herbert Asbury
The Future of an Illusion by Sigmund Freud
Modern Chess Openings by Richard Clevin Griffith and John Herbet White
The Daughters of Time by Josephine Tey
Death Comes for the Archbishop by Willa Cather
The Case-Book of Sherlock Holmes,” by Arthur Conan Doyle
Le Temps retrouvé by Marcel Proust (in French)
The Bridge of San Luis Rey by Thornton Wilder
Films
The Jazz Singer
Chicago
When Boys Leave Home
Uncle Tom’s Cabin
Wings
Tarzan and the Golden Lion
The King of Kings, directed by Cecil B. DeMille
The Battle of the Century, starring Laurel and Hardy
The Lodger, a film by Alfred Hitchcock
Metropolis, a film by Fritz Lang and Thea von Harbou
Musical Compositions
“Back Water Blues,” “Preaching the Blues” and “Foolish Man Blues” (Bessie Smith)
“The Best Things in Life Are Free,” from the musical “Good News” (George Gard “Buddy” De Sylva, Lew Brown, Ray Henderson)
“Billy Goat Stomp,” “Hyena Stomp” and “Jungle Blues” (Ferdinand Joseph Morton)
“Black and Tan Fantasy” and “East St. Louis Toodle-O” (Bub Miley, Duke Ellington)
“Can’t Help Lovin’ Dat Man” and “Ol’ Man River,” from the musical “Show Boat” (Oscar Hammerstein II, Jerome Kern)
“Diane” (Erno Rapee, Lew Pollack)
“Funny Face” and “’S Wonderful,” from the musical “Funny Face” (Ira and George Gershwin)
“(I Scream You Scream, We All Scream for) Ice Cream” (Howard Johnson, Billy Moll, Robert A. King)
“Mississippi Mud” (Harry Barris, James Cavanaugh)
“My Blue Heaven” (George Whiting, Walter Donaldson)
“Potato Head Blues” and Gully Low Blues” (Louis Armstrong)
“Puttin’ on the Ritz” (Irving Berlin)
“Rusty Pail Blues,” “Sloppy Water Blues” and “Soothin’ Syrup Stomp” (Thomas Waller)
There are more music and sound recordings in the public domain than I've listed and you can see more at this link PD Info