APA-viite (7. p.)
Siegfried, T., & Frey, M. (2002). Strange matters: Undiscovered ideas at the frontiers of space and time. Joseph Henry Press.
Chicago-viite (17. p.)
Siegfried, Tom, ja Matthew Frey. Strange Matters: Undiscovered Ideas at the Frontiers of Space and Time. Washington, District of Columbia: Joseph Henry Press, 2002.
MLA-viite (9. p.)
Siegfried, Tom, ja Matthew Frey. Strange Matters: Undiscovered Ideas at the Frontiers of Space and Time. Joseph Henry Press, 2002.
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