"O'Bannon introduced [Ridley] Scott to the artwork of H. R. Giger; both of them felt that his painting Necronom IV was the type of representation they wanted for the film's [Alien] antagonist and began asking the studio to hire him as a designer". 

"The design of the 'chestburster' was inspired by Francis Bacon's 1944 painting Three Studies for Figures at the Base of a Crucifixion"

"The mouth of the triptych's central figure was also inspired by the nurse's scream in film director Sergei Eisenstein's Odessa Steps massacre sequence in The Battleship Potemkin (1925)"