[1] Einstein A, Podolsky B and Rosen N 1935 Phys. Rev.
47 777

[2] Cirac I et al 2001 Phys. Rev. Lett. 86 544

[3] Yu S and Liu N L 2005 Phys. Rev. Lett. 95
150504

[4] G\"{uhne O et al 2006 Phys. Rev. A 74
010301(R)

[5] Zhang C J, Zhang Y S, Zhang S and Guo G C 2007 Phys.
Rev. A 76 012334

[6] Osborne T J 2005 Phys. Rev. A 72 022309

[7] Wang X G and Zanardi P 2003 Phys. Rev. A 66
044303

[8] Rungta P et al 2001 Phys. Rev. A 64 042315

[9] Lin Q et al 2007 Chin. Phys. Lett. 24 1809

[10] Fiurasek J 2004 Phys. Rev. A 70 032308

[11] Vidal G, Jonathan D and Nielsen M A 2000 Phys. Rev.
A 62 012304

[12] Vedral V, Plenio M B 1998 Phys. Rev. A 57
1619