Authentication Score 3
Citation
Skinner, B. F. Contingencies of Reinforcement: A Theoretical Analysis. Appleton-Century-Crofts, 1969, ch. 9.
Man and machine
Hubbard, Elbert. A Thousand & One Epigrams: Selected from the Writings of Elbert Hubbard. The Roycrofters, 1911.
Star Wars: Episode VI - Return of the Jedi. Directed by Richard Marquand, Lucasfilm Ltd., 1983.
Wells, H. G. "The Idea of a Permanent World Encyclopaedia." Harper's Magazine, Apr. 1937.
Ellis, Havelock. Little Essays of Love and Virtue. George H. Doran Company/A & C Black, 1922, ch. 7.