On-sale date from Comic Reader #112.
Credits for pencils and inks confirmed from Julius Schwartz's editorial records, provided by DC Comics.
Writer credit by Martin O'Hearn; inker credit by Bob Hughes. Pencils previously credited to Sam Citron. Based on Martin O’Hearns blog:
and comparing this story to Citron’s known work on Classics Illustrated 10 [HRN 140] and the DC Mr. District Attorney series, this credit has been changed to Pete Riss.
Various intuders in the Fortress illustrated with details from Action Comics (DC, 1938 series) #241, World's Finest Comics (DC, 1941 series) #100, Superman's Pal, Jimmy Olsen (DC, 1954 series) #97, World's Finest Comics (DC, 1941 series) #164, and Superman's Girl Friend, Lois Lane (DC, 1958 series) #87.
Original inking credit of George Klein, as credited in this reprint, changed to match credits from Superman #148 index.