On-sale date from copyright registration.
Credits for script, pencils and inks confirmed from Julius Schwartz's editorial records, provided by DC Comics.
Letters from Gary Trenet, James Higgins, and Rory Chase.
Copies of DC editorial records credit the pencils and inks to Frank Giacoia. Mark Evanier, Jim Vadeboncoeur, and Gene Reed agree that Jack Kirby did the pencils on this story.