On sale date from the 1981 Library of Congress copyright records (cocatalog.loc.gov). Same date given in Amazing Heroes #2, Comic Reader #191, Comics Journal #64, DC Coming Attractions #55, and Daily Planet vol. 81 #7.
This issue has variants:
Superman [Clark Kent]; Lois Lane; Jimmy Olsen; Perry White; Lex Luthor (villain, disguised as Dominus, and in flashback disguised as Mr. Slesar); Roger (villain); Green Lantern [Hal Jordan]; Phantom Zone inhabitants [Mon-El; Jax-Ur; two unnamed prisoners]; Supergirl (flashback); Urko the Terrible (flashback, villain); Fire-People (flashback, villains); "King" Andrews (flashback, villain); Michael Andrews (flashback); Brainiac (flashback); Koko (flashback); Professor Kimda (flashback); Kandorians (flashback); Jor-El (statue); Lara (statue); Wonder Woman (statue); Batman (statue); Robin (statue); Flash [Barry Allen] (statue); Jonathan Kent (statue); Martha Kent (statue); Krypto (statue)