中国科学院数学与系统科学研究院期刊网
Classification of Type I Time-Like Hyperspaces with Parallel Conformal Second Fundamental Forms in the Conformal Space
Chang Xiong NIE, Da Ping TIAN, Chuan Xi WU
Acta Mathematica Sinica, Chinese Series . 2011, (1): 125 -136 .  DOI: 10.12386/A2011sxxb0014