McIntosh, Jane
The practical archaelogist: how we know what we know about the past
Checkmark Books, 1999
Buku Referensi
Cochrane, Susan H.
Fertility and education: what do we really know?
Johns Hopkins University Press, 1979
Buku Teks SO
Overstreet, Harry
What we must know about communism
Norton, 1958
Buku Teks SO
Rabe, Cynthia Barton
The innovation killer: how what we know limits what we can imagine-- and what smart companies are doing about it
American Management Association, 2006
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What do products/services cost how do we know?
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