31 sources
The Avengers (vol. 1) #195 (May 1980): "Assault on a Mind Cage!"Captain America (vol. 1) #245 (May 1980): "The Calypso Connection!"Daredevil (vol. 1) #164 (May 1980): "Exposé"The Defenders (vol. 1) #83 (May 1980): "End of the Tunnel"Detective Comics (vol. 1) #490 (May 1980): "Lightning Strikes Out!"The Empire Strikes Back (1980)Friday the 13th (1980)Ghost Rider (vol. 2) #44 (May 1980): "Cloak of Crimson - Soul of Dust!"Green Lantern (vol. 2) #128 (May 1980): "The Green That Got Away!"
Howard the DuckJustice League of America (vol. 1) #178 (May 1980): "The Chess-Master of Mars"Legion of Super-Heroes (vol. 2) #263 (May 1980): "Day of Judgment"The Man-Thing (vol. 2) #4 (May 1980): "Death-Knell"Marvel Spotlight (vol. 2) #6 (May 1980): "The Saga of Star-Lord"Marvel Team-Up (vol. 1) #93 (May 1980): "Rags to Riches!"Marvel Two-in-One (vol. 1) #63 (May 1980): "Suffer Not a Warlock to Live!"Master of Kung Fu #88 (May 1980): "Warriors of the Golden Dawn Part 6: The Leopard and the Dove"The Micronauts (vol. 1) #17 (May 1980): "...The Harder They Fall!"The New Adventures of Superboy #5 (May 1980): "Secret of the Super-Power Failures"Pac-Man (22 May 1980)Peter Parker, The Spectacular Spider-Man #42 (May 1980): "Give Me Liberty or Give Me Death!"Reid Fleming, World's Toughest Milkman #1 (May 1980)ROM #6 (May 1980): "Dog Day Afternoon!"The Savage She-Hulk #4 (May 1980): "The She-Hulk Strikes Back!"The Savage Sword of Conan #52 (May 1980): "Conan the Liberator"Spider-Woman (vol. 1) #26 (May 1980): "The Blades of the Grinder!"Star Wars: Episode V - The Empire Strikes Back (1980)Thor (vol. 1) #295 (May 1980): "The Price--and the Pride!"The Uncanny X-Men (vol. 1) #133 (May 1980): "Wolverine: Alone!"The Warlord (vol. 1) #33 (May 1980): "Birds of Prey"