APA (7 वां संस्करण) प्रशस्ति पत्र

Penrose, R. (2004). The road to reality: A complete guide to the laws of the universe (First American edition.). A.A. Knopf.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Penrose, Roger. The Road to Reality: A Complete Guide to the Laws of the Universe. First American edition. New York: A.A. Knopf, 2004.

एमएलए (8वां संस्करण) प्रशस्ति पत्र

Penrose, Roger. The Road to Reality: A Complete Guide to the Laws of the Universe. First American edition. A.A. Knopf, 2004.