On-sale date from copyright registration.
Ira Schnapp letterer credit via Todd Klein through a post from his blog Kleinletters, 16 October 2016 (retrieved 19 November 2016, http://kleinletters.com/Blog/star-spangled-schnapp/).
Script credit from Evans' estate (Comics Buyers Guide, June 15, 1990).
Art credits from Bob Hughes, Gene Reed, Merlin Haas, Edgar Loftin, and Allen Ross. Loftin and Ross question Mayer inks credit. Bob Bailey argues Bob Oksner base with Mayer heads.