Originally published in magazine form in ADVENTURE COMICS (Vol. 1) #304, January 1963.
All Rights reserved to DC Comics.
Reprinted in ADVENTURE COMICS (Vol. 1) #403, March 1971; in ADVENTURE COMICS DIGEST (Vol. 1) #499, May 1983; in LEGION OF SUPER-HEROES ARCHIVES Volume One, 1991; in SHOWCASE PRESENTS: LEGION OF SUPER-HEROES, Vol. 1, April 2007 & in LEGION OF SUPER-HEROES 1050 YEARS OF THE FUTURE TPB, 2008.
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