Harland, W. B. (1989). A geologic time scale 1989. Cambridge University Press.
Chicago Style (17th ed.) CitationHarland, Walter Brian. A Geologic Time Scale 1989. New York: Cambridge University Press, 1989.
MLA引文Harland, Walter Brian. A Geologic Time Scale 1989. Cambridge University Press, 1989.
警告:這些引文格式不一定是100%准確.