http://reply.papertrans.cn/3/221/22040/22040-21.png
http://reply.papertrans.cn/3/221/22040/22040-22.png
http://reply.papertrans.cn/3/221/22040/22040-23.png
Submitted on: 18 January 2000.
Revised on: 16 February 2000.
Accepted on: 28 February 2000.
MINERVA---SPRINGER
Submitted on: 11 October 2011.
Revised on: 07 November 2011.
Accepted on: 19 November 2011.
MINERVA
http://reply.papertrans.cn/3/221/22040/22040-26.png
http://reply.papertrans.cn/3/221/22040/22040-27.png
http://reply.papertrans.cn/3/221/22040/22040-28.png
http://reply.papertrans.cn/3/221/22040/22040-29.png
http://reply.papertrans.cn/3/221/22040/22040-30.png