Encyclopedia of earth sciences : volume 1
E. Julius Dasch, editor in chief
MacMillan Reference USA, 1996
 Buku Referensi
International encyclopedia of the social sciences : volume 1 & 2
editor, David L. Sills
Macmillan Co. & The Free Press, 1968
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Macmillan encyclopedia of sciences : The Earth
New York : macmillan Library reference USA, 1997,
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Macmillan encyclopedia of sciences : Life on Earth
New York : Macmillan Library Reference, 1997,
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Companion encyclopedia of the history and philosophy of the mathematical sciences; Volume 2
edited by I. Grattan-Guinness
Routledge, 1994
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