Court, W.H.B.
Oxford University Press, 1953
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Khairul Rizal, author
Badan Perencanaan Pembangunan Nasional (BAPPENAS), 2019
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Collins, Earl A., author
Webster, 1955
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Achmad Alfian, author
Fakultas Teknik Universitas Indonesia, 2013
UI - Skripsi (Membership)
Wallace, Robert, author
Time-Life Books, 1967
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