APA-ийн эшлэл(7 дахь хэвлэлт)

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

Чикаго-гийн эшлэл (17 дахь хэвлэлт)

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

MLA -ийн эшлэл (9 дэх хэвлэлт)

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