एपीए उद्धरण

Penrose, R. (2010). Cycles of time: An extraordinary new view of the universe. The Bodley Head.

शिकागो स्टाइल उद्धरण

Penrose, Roger. Cycles of Time: An Extraordinary New View of the Universe. London: The Bodley Head, 2010.

एमएलए उद्धरण

Penrose, Roger. Cycles of Time: An Extraordinary New View of the Universe. The Bodley Head, 2010.