Katz, William A., 1924-, author
McGraww-Hill, 1992
Buku Teks
Americana Corporation, 1977
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Americana Corporation, 1964
Buku Referensi
Lederberg, Joshua, editor-in-chief
Academic Press, 1992
Buku Referensi
Encyclopaedia Britannica Inc., 1967
Buku Referensi