Wolfram, Walt, 1941-
American English: dialects and variation
Wiley Balckwell, 2016
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Dialects of English : studies in grammatical variation
edited by Peter Trudgill and J.K. Chambers
Longman, 1991
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Jaschke, H.A.
Tibetan-English dictionary : with special reference to the prevailing dialects
London : Routledge & Kegan Paul Ltd., 1949.
 Buku Teks
Jaschke, H. A.
A Tibetan-English dictionary with special reference to the prevailing dialects
Trubner and Co. Ludgate Hill, 1882
 Buku Referensi
Malmstrom, Jean
Dialects USA
National Council of Teachers of English, 1963
 Buku Teks SO