Brown, Penelope
Politeness : some universals in language usage
Cambridge University Press , 1987
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Sandler, Wendy
Sign language and linguistic universals
Cambridge University Press, 2006
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Bloomfield, Leonard
Language
Holt, Rinehart and Winston, 1961
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Sign language and linguistic universals / Wendy Sandler, Diane Lillo-Martin
Cambridge University Press, 2006
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Beard, Adrian
Language change
Routledge, 2004
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