Quotes from work
Superman

Superman was a daily newspaper comic strip which began on January 16, 1939, and a separate Sunday strip was added on November 5, 1939. These strips ran continuously until May 1966. In 1941, the McClure Syndicate had placed the strip in hundreds of newspapers. At its peak, the strip, featuring Superman, was in over 300 daily newspapers and 90 Sunday papers, with a readership of over 20 million.

“Superman! Champion of the oppressed. The physical marvel who had sworn to devote his existence to helping those in need.”

Jerry Siegel Superman

First introduction http://superman.ws/tales2/action1/?page=1 of "Superman" as "Clark Kent" in Action Comics #1 (June 1938)

“In the January, 1933 issue of "SCIENCE FICTION" appeared a story I had written in 1932 entitled, "The Reign of the Superman." I used the pseudonym "Herbert S. Fine" which combined the name of a cousin of mine together with my mother's maiden name.
After the publication of "Reign of the Superman", it occurred to me that a different version of Superman could be the basis of an extremely powerful and successful comic book. And so I originated, together with Joe Shuster, the comic book "THE SUPERMAN", back in 1933.”

Jerry Siegel Superman

"Happy Anniversary, Superman!" http://theages.superman.ws/siegel.php (1983)

“The Reign of the Superman”

Jerry Siegel Superman

Title of Siegel's first published story of a "Superman" — one who was villainous. He later realized a character with super-powers could make a great comic book hero. (1933)