Husserl, Edmund
The Shorter logical investigations
Routledge, 2001
 Buku Teks SO
Hoefnagels, Marielle
Biology : concepts and investigations
McGraw-Hill, Higher Education, 2009
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Bregman, Allyn A.
Laboratory investigations in cell biology
John Wiley & Sons, 1983
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Gardner, Eldon J.
Genetics laboratory investigations
Burgess, 1975
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Chemical investigations for changing times
by Lawrence W. Scott [and others]
Burgess, 1976
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