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Buku Teks
Trotsky, Leon
The University of Michigan Press, 1932
Buku Teks
Boyle, Peter G., author
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Buku Teks
Mock, James R., author
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Buku Teks
Prastissa Amallia, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2015
UI - Makalah dan Kertas Kerja