edited by Martin E. Liggins, David L. Hall, James Llinas
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Buku Referensi
Searles, William H.
John Wiley & Sons, 1949
Buku Referensi
Armstrong, Michael
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Buku Referensi
edited by Jeffrey J. Magnavita
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Buku Teks
edited by John S. Dryzek, Bonnie Honig, Anne Phillips
Oxford University Press, 2008
Buku Referensi