Dobbin, Christine
Oxford University Press, 1972
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Andi Hamzah
[publisher not identified], [date of publication not identified]
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Artikel Jurnal
Enthoven, R.E.
The Clarendon Press, 1924
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Daniel Pascoe [and eight others]; editor, Robertus Robert dan Todung Mulya Lubis
Marjin Kiri kerjasama dengan Perhimpunan Pendidikan Demokrasi, 2016
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