[1]Fachbereich Mathematik, Universitat Duisburg-Essen, Campus Essen 45117 Essen, Germany;
[2]Philipps-Universitat Marburg, Fachbereich Mathematik und Informatik 35032 Marburg, Germany;
[3]School of Mathematics, Statistics and Computer Science, College of Science University of Tehran, Tehran, Iran;
极大理想 金属性 Betti数 同源 权力 多项式环 子模块 剩余类域;