Dick, S. J. (1998). Life on other worlds: The 20th-century extraterrestrial life debate. Cambridge: Cambridge University Press.
Παραπομπή Chicago StyleDick, Steven J. Life On Other Worlds: The 20th-century Extraterrestrial Life Debate. Cambridge: Cambridge University Press, 1998.
Παραπομπή MLADick, Steven J. Life On Other Worlds: The 20th-century Extraterrestrial Life Debate. Cambridge: Cambridge University Press, 1998.
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