Submitted on: 20 February 1999.
Revised on: 20 April 1999.
Accepted on: 03 May 1999.
___________________Analysis Mathematica---SPRINGER INT PUBL AG
Submitted on: 01 April 2005.
Revised on: 05 May 2005.
Accepted on: 18 June 2005.
___________________Analysis Mathematica---SPRINGER INT PUBL AG
http://reply.papertrans.cn/1/16/1574/1574-33.png
Submitted on: 09 October 2014.
Revised on: 14 December 2014.
Accepted on: 12 January 2015.
___________________Analysis Mathematica---SPRINGER INT PUBL AG
Submitted on: 04 December 2014.
Revised on: 17 March 2015.
Accepted on: 01 May 2015.
___________________Analysis Mathematica---SPRINGER INT PUBL AG
Submitted on: 09 December 2009.
Revised on: 21 January 2010.
Accepted on: 24 February 2010.
___________________Analysis Mathematica---SPRINGER INT PUBL AG