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Amsterdam Academic Archive, 2005
Buku Teks
Raymond Hickey, editor
Wiley-Blackwell, 2010
Buku Teks
Drinka, Bridget, 1951-, author.
Cambridge University Press, 2017
Buku Teks
Winford, Donald, author
Blackwell Publishing, 2003
Buku Teks
Weinreich, Uriel
Mounton , 1974
Buku Teks