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Hughes, Christopher
Routledge , 1997
Buku Teks
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Buku Teks
edited by Ulrich Ammon, Norbert Dittmar, Klaus J. Mattheier
Walter de Gruyter, 1987
Buku Referensi
edited by Ulrich Ammon, Norbert Dittmar, Klaus J. Mattheier
Walter de Gruyter, 1988
Buku Referensi