Cita APA (7th ed.)

Coles, P., & Ellis, G. (1997). Is the Universe Open or Closed?: The Density of Matter in the Universe. Cambridge University Press.

Cita Chicago (17th ed.)

Coles, Peter, i George Ellis. Is the Universe Open or Closed?: The Density of Matter in the Universe. Cambridge, United Kingdom: Cambridge University Press, 1997.

Cita MLA (9th ed.)

Coles, Peter, i George Ellis. Is the Universe Open or Closed?: The Density of Matter in the Universe. Cambridge University Press, 1997.