Bone, Hough Alvin
McGraw-Hill, 1981
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Adithia Ramadhan
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2012
UI - Skripsi (Membership)
Medvic, Stephen K.
Routledge, Taylor & Francis Group, 2018
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Heard, Alexander
Anchor Books Doubleday and Company, 1962
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Hugn A. Bone
McGraw-Hill , 1976
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