Pencils credit from Bob Klein, Gene Reed, Mike Tiefenbacher, and Bob Hughes. Pat Lang and Craig Delich credit Jim Mooney. Letters credit from Todd Klein via his Klein Letters blog (18 September 2016, http://kleinletters.com/Blog/ira-schnapp-in-worlds-finest-comics-part-1/).
Previously appeared in August 1962 issues.
Writer credit from Martin O'Hearn.