摘要
Let G be an arbitrary group, finite or infinite, and A be a G-graded ring, i. e. A is an associative ring and A<sub>g</sub> （direct sum of additive subgroups A<sub>g</sub> ）with property: A<sub>g</sub>· A<sub>h</sub> A<sub>gh</sub>, g, h∈G. Let M be a graded A-module, i. e. M is right A-module and M<sub>g</sub>
基金
Project supported by the National Natural Science Foundation of China.
