International encyclopedia of the social sciences : social science quotation, volume 19
David L. Sills, Robert K. Merton, editors
MacMilan Publishing, 1991
 Buku Referensi
Encyclopedia of science, technology and ethics
Thompson Gale, 2005
 Buku Teks
International encyclopedia of political science
SAGE Reference, 2011
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Encyclopedia of science and technology Vol.1
editor, in.chief, R.P. Jain; editors, V.K. Gendhi, Artul Amand, Anuj Kohli, Anil Sharga
Crest Publishing House, 1998,
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Encyclopedia of science and technology Vol.2
Crest Publishing House, 1998,
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