Science China Mathematics > 2007 > 50 > 2 > 231-239
Source
Abstract
Identifiers
journal ISSN : | 1674-7283 |
journal e-ISSN : | 1869-1862 |
DOI | 10.1007/s11425-007-2077-x |
Science China Mathematics > 2007 > 50 > 2 > 231-239
journal ISSN : | 1674-7283 |
journal e-ISSN : | 1869-1862 |
DOI | 10.1007/s11425-007-2077-x |