On-sale date from Direct Currents in Sea Devils #30 and copyright registration.
Credits confirmed by Bob Bailey, Bob Hughes, and Gene Reed.
In The Comic Reader #27 (July 1964), George Kashdan is credited with writing the Blackhawk fillers. Info per Nick Caputo.
Trade requests from Charles Keebler, Marshal Lanz, John Daly, Brian Rog, Dick Loo, Steve Miller, Edward Bass, Joe Deliz, Mike Mooberry, James E. Coon, LaVern Loretz, Nicholas De Larbe, Mark Nedderman, Dennis Hamer, and Larry Lindokken.