Submitted on: 29 September 2010.
Revised on: 15 October 2010.
Accepted on: 09 November 2010.
Language Variation and Change---CAMBRIDGE UNIV PRESS
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Submitted on: 20 May 2013.
Revised on: 30 June 2013.
Accepted on: 13 July 2013.
Language Variation and Change
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