Superman

Grant Morrison and Frank Quitely wrote All-Star Superman as a distillation of the character Siegel and Shuster created, outside continuity: the origin, Lois, Lex Luthor and the Fortress retold as a last twelve labours, deliberately drawing on the full history of the comic.

Richard Donner's film adapts the comic's origin directly: the destruction of Krypton, the infant sent to Earth, the Kents, the Daily Planet and Lois Lane. The character first appeared in Action Comics #1 (1938) before this series was launched.

Jerry Siegel credited The Scarlet Pimpernel, with Zorro, as an inspiration for Superman, particularly the dual identity: mild-mannered Clark Kent is the Pimpernel's harmless public face.

Jerry Siegel credited Zorro along with The Scarlet Pimpernel as inspirations for Superman, particularly the concept of a dual identity as mild-mannered reporter Clark Kent.

Wylie's Hugo Danner is the most direct literary ancestor of Superman: a man with the proportionate strength of an insect, who can leap enormous distances and whom bullets cannot hurt, and who struggles to find a use for his power. Comics historians regularly name it as a source for Siegel and Shuster, whose first Superman leaps rather than flies. https://en.wikipedia.org/wiki/Gladiator_(novel)

The claim is about Doc Savage, the pulp hero this novel introduced. Superman borrowed from him openly:

• The Man of Steel echoes the Man of Bronze
• Both heroes retreat to a Fortress of Solitude in the Arctic, Doc Savage's first

Siegel and Shuster read the Doc Savage pulps, and the connection is standard in histories of the character.

Siegel named Burroughs's John Carter among his sources. The claim is about A Princess of Mars, the first Barsoom book: Carter is an Earthman whose strength and leaps are superhuman on a planet of lower gravity, and early Superman explained his own powers the same way, as a man from a heavier world on Earth.