Who directed 'Citizen Kane' (1941)?

Who directed '2001: A Space Odyssey' (1968)? Who directed 'Titanic' (1997)? Who directed 'Taxi Driver' (1976)? Who directed 'Inception' (2010)? Who directed 'Back to the Future' (1985)? Who directed 'E.T. the Extra-Terrestrial' (1982)? Who directed 'Alien' (1979)? Who directed 'The Terminator' (1984)?