About author:LI Yun-hui(1977-), female, native of Yichang, Hubei, a teacher of Yuan’an Senior Middle School, M.S.D., engages in commuatative algebra; TANG Gao-hua(1965-), male, native of Guilin, Guangxi, a professor of Guangxi Teacher’s College, Ph.D., engages in homological algebra.
Supported by:
Supported by the Natural Sciences Foundation of Guangxi Province(0575052, 0640070); Supported by the Innovation Project of Guangxi Graduate Education(2006106030701M05); Supported by the Scientific Research Foundation of Guangxi Educational Committee(200707LX233;