http://reply.papertrans.cn/1/77/7694/7694-31.png
http://reply.papertrans.cn/1/77/7694/7694-32.png
Submitted on: 07 July 2009.
Revised on: 05 August 2009.
Accepted on: 25 August 2009.
___________________DUKE MATHEMATICAL JOURNAL---DUKE UNIV PRESS
Submitted on: 21 January 2015.
Revised on: 12 April 2015.
Accepted on: 29 April 2015.
___________________DUKE MATHEMATICAL JOURNAL---DUKE UNIV PRESS
Submitted on: 24 March 2005.
Revised on: 18 July 2005.
Accepted on: 18 August 2005.
___________________DUKE MATHEMATICAL JOURNAL---DUKE UNIV PRESS
Submitted on: 20 January 2005.
Revised on: 01 March 2005.
Accepted on: 15 April 2005.
___________________DUKE MATHEMATICAL JOURNAL---DUKE UNIV PRESS