Submitted on: 26 October 2009.
Revised on: 06 February 2010.
Accepted on: 16 March 2010.
___________________Finance Research Letters---ACADEMIC PRESS INC ELSEVIER SCIENCE
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Submitted on: 17 December 2017.
Revised on: 07 March 2018.
Accepted on: 27 March 2018.
___________________Finance Research Letters---ACADEMIC PRESS INC ELSEVIER SCIENCE
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