This issue is a variant of The Eternals (Marvel, 1976 series) #15 [30¢ Cover Price]. There exist further variants.
Alterations on the Hulk by John Romita.
Letters credit to Danny Crespi confirmed from Danny Crespi Files, posted via the Comics History Exchange page on Facebook by Todd Klein (1 April 2017). Originally tentatively credited to Gaspar Saladino.