APA-viite

Penrose, R., & Roger Penrose; foreword by Martin Gardner. (1991). The: Concerning computers, minds, and the laws of physics. New York, N.Y: Penguin Books.

Chicago-tyylinen lähdeviittaus

Penrose, Roger, ja Roger Penrose; foreword by Martin Gardner. The: Concerning Computers, Minds, and the Laws of Physics. New York, N.Y: Penguin Books, 1991.

MLA-viite

Penrose, Roger, ja Roger Penrose; foreword by Martin Gardner. The: Concerning Computers, Minds, and the Laws of Physics. New York, N.Y: Penguin Books, 1991.

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