Justice League of America — DC Comics
Issue: #13
Last valuation update: 2022-07-02
The JLA find themselves on a far off planet where they must battle robotic versions of themselves in order to save that planet - and earth- from alien conquest. Using scientific explanation & reasoning, Gardner Fox proceeds to demonstrate how our heroes can overcome their never tiring counterparts. This story is not only great entertainment, but also scientifically educational.
First appearances: Sforll
Creators: Gardner Fox, Murphy Anderson, Mike Sekowsky, Bernard Sachs, Ira Schnapp, Gaspar Saladino, Julius Schwartz
Characters: Batman, Superman, Martian Manhunter, Hal Jordan, Aquaman, Barry Allen, Wonder Woman, Green Arrow, Jimmy Olsen, Snapper Carr, Roy Harper, Tom Kalmaku, Sforll