Green Lantern (1960 2nd Series DC) #68
Published Apr 1969 by DC.

"I Wonder Where the Yellow Went!", script by Denny O'Neil
pencils by Gil Kane, inks by Joe Giella
An alien invader disguises hmself as a scientist who claims to have discovered the way to eliminate Green Lantern's power ring's yellow weakness, but in reality the process renders the ring powerless after a few days.

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