17 sources
Amazing Adventures (vol. 2) #12 (May 1972): "Iron Man: D.O.A."The Amazing Spider-Man (vol. 1) #108 (May 1972): "Vengeance from Viet Nam!"Captain America (vol. 1) #149 (May 1972): "All the Colors -- of Evil!"Daredevil (vol. 1) #87 (May 1972): "From Stage Left, Enter: Electro!"Justice League of America (vol. 1) #98 (May 1972): "No More Tomorrows!"Marvel Premiere #2 (May 1972): "The Hounds of Helios"Marvel Spotlight (vol. 1) #3 (May 1972): "The Thing in the Cellar!"Marvel Team-Up (vol. 1) #2 (May 1972): "And Spidey Makes Four!"Mary Had a Little Lamb (12 May 1972)Red Wolf (vol. 1) #1 (May 1972): "A Thunder of War Drums!"Sgt. Fury and His Howling Commandos (vol. 1) #98 (May 1972): "Top Secret: Dugan's Deadly Dozen"Sub-Mariner (vol. 1) #49 (May 1972): "The Dreamstone"
Superman's Pal, Jimmy OlsenThor (vol. 1) #199 (May 1972): "If This Be Death..!"The Tomb of Dracula (vol. 1) #2 (May 1972): "The Fear Within!"Valiant and TV21 (13 May 1972): "Kid Pharaoh"