中国科学院数学与系统科学研究院期刊网
The r-Comparability and r-Power Comparability of Modules
Qi Sheng LI(1); Wen Ting TONG(
Acta Mathematica Sinica, Chinese Series . 2007, (3): 567 -576 .  DOI: 10.12386/A2007sxxb0067