Submitted on: 28 June 1999.
Revised on: 11 September 1999.
Accepted on: 17 October 1999.
___________________INTERNATIONAL JOURNAL OF MATHEMATICS AND MATHEMATICAL SCIENCES
http://reply.papertrans.cn/2/138/13724/13724-22.png
Submitted on: 02 April 2003.
Revised on: 23 April 2003.
Accepted on: 20 May 2003.
___________________INTERNATIONAL JOURNAL OF MATHEMATICS AND MATHEMATICAL SCIENCES
Submitted on: 08 June 2020.
Revised on: 25 September 2020.
Accepted on: 24 October 2020.
___________________INTERNATIONAL JOURNAL OF MATHEMATICS AND MATHEMATICAL SCIENCES
http://reply.papertrans.cn/2/138/13724/13724-25.png
Submitted on: 26 April 2008.
Revised on: 21 June 2008.
Accepted on: 30 July 2008.
___________________INTERNATIONAL JOURNAL OF MATHEMATICS AND MATHEMATICAL SCIENCES
Submitted on: 10 February 2006.
Revised on: 26 May 2006.
Accepted on: 10 July 2006.
___________________INTERNATIONAL JOURNAL OF MATHEMATICS AND MATHEMATICAL SCIENCES
http://reply.papertrans.cn/2/138/13724/13724-28.png
Submitted on: 11 May 2020.
Revised on: 29 June 2020.
Accepted on: 21 July 2020.
___________________INTERNATIONAL JOURNAL OF MATHEMATICS AND MATHEMATICAL SCIENCES
Submitted on: 28 November 2014.
Revised on: 31 December 2014.
Accepted on: 14 January 2015.
___________________INTERNATIONAL JOURNAL OF MATHEMATICS AND MATHEMATICAL SCIENCES