Submitted on: 12 September 2013.
Revised on: 20 September 2013.
Accepted on: 27 September 2013.
Philosophia Mathematica
Submitted on: 06 January 2006.
Revised on: 26 January 2006.
Accepted on: 16 February 2006.
Philosophia Mathematica
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http://reply.papertrans.cn/3/245/24458/24458-24.png
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Submitted on: 29 November 2010.
Revised on: 07 December 2010.
Accepted on: 20 December 2010.
Philosophia Mathematica---OXFORD UNIV PRESS INC
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Submitted on: 18 August 2016.
Revised on: 27 September 2016.
Accepted on: 08 October 2016.
Philosophia Mathematica---OXFORD UNIV PRESS INC
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Submitted on: 22 January 2005.
Revised on: 22 February 2005.
Accepted on: 04 March 2005.
Philosophia Mathematica