Possible Stein inks per Mark Evanier and Nick Caputo after studying his concurrent work. In conversations with Greg Theakston Stein said he did not ink any Challengers stories but it's possible he had forgotten.
For lack of letters of comment, a description of Jack Kirby's career is given.
Previously inker listed as Marvin Stein. Per Stein's conversations with Greg Theakston, he did not ink any Challengers stories.