(1991). Postprincipia: Gravitation for physicists and astronomers. Singapore: World Scientific.
शिकागो स्टाइल उद्धरणPostprincipia: Gravitation for Physicists and Astronomers. Singapore: World Scientific, 1991.
एमएलए उद्धरणPostprincipia: Gravitation for Physicists and Astronomers. Singapore: World Scientific, 1991.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.