Acta Mathematica Sinica, English Series
Acta Mathematica Sinica, English Series > 2004 > 20 > 1 > 175-180
Acta Mathematica Sinica, English Series > 2004 > 20 > 2 > 283- 292
Acta Mathematica Sinica, English Series > 2004 > 20 > 2 > 283-292
Acta Mathematica Sinica, English Series > 2004 > 20 > 1 > 175-180
Acta Mathematica Sinica, English Series > 2004 > 20 > 2 > 283- 292
Acta Mathematica Sinica, English Series > 2004 > 20 > 2 > 283-292