Penrose, R. (2011). Roger Penrose: Collected works. Oxford ; New York : Oxford University Press.
Chicago-čujuhus (17. p.)Penrose, Roger. Roger Penrose: Collected Works. Oxford ; New York : Oxford University Press, 2011.
MLA-čujuhus (9. p.)Penrose, Roger. Roger Penrose: Collected Works. Oxford ; New York : Oxford University Press, 2011.
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