|   [1] Cao J, Dai Bo, Mei Jiaqiang. An extension of Perelman’s soul theorem for singular spaces. arXiv: 0706.0565 
 
[2] Cheeger J, Gromoll D. The splitting theorem for manifolds of nonnegative Ricci curvature. J Differential Geometry, 1971/1972, 6: 119–128 
 
[3] Cheeger J, Gromoll D. On the structure of complete manifolds of nonnegative curvature. Annals of Math, 1972, 96: 413–443 
 
[4] Perelman G. A. D. Alexandrov’s spaces with curvatures bounded from below. II. Preprint 
 
[5] Perelman G. Proof of the soul conjecture of Cheeger and Gromoll. J Differential Geom, 1994, 40(1): 209–212 
 
[6] Wu H. An elementary method in the study of nonnegative curvature. Acta Math, 1979, 142(1/2): 57–78 
 
[7] Yau S -T. A review of complex differential geometry. Proc Sympos Pure Math, 1991, 52(2): 619–625 
 
[8] Zheng Fangyang. Complex differential geometry. AMS/IP Studies in Advanced Mathematics, 18. Providence, RI: American Mathematical Society; Boston, MA: International Press, 2000  |