[1] Hawking S W 1972 Commun Math. Phys. 25 152

[2] Hawking S W 1975 Commun Math. Phys. 43 199

[3] Bardeen J M, Carter B and Hawking S W 1973 Commun.
Math. Phys. 31 161

[4] Smarr L 1973 Phys. Rev. Lett. 30 71

[5] Jacobson T 1995 Phys. Rev. Lett. 75 1260

[6] Eling C, Guedens R and Jacobson T 2006 Phys. Rev.
Lett. 96 121301

[7] Hayward S A 2004 Phys. Rev. Lett. 93 251101

[8] Ashtekar A and Krishnan B 2002 Phys. Rev. Lett.
89 261101

[9] Gong Y and Wang A 2007 Phys. Rev. Lett. 99
211301

[10] Rogatko M 2007 Phys. Rev. D 75 124015

[11] Padmanabhan T 2005 Phys. Rept. 406 49

[12] Padmanabhan T 2002 Class. Quan. Grav. 19 5387

[13] Padmanabhan T 2004 Class. Quant. Grav. 21
4485

[14] Akbar M and Cai R G 2007 Phys. Lett. B 648
243

[15] Cai R G and Cao L M 2007 Phys. Rev. D 75
064008

[16] Sheykhi A, Wang B and Cai R G 2007 Phys. Rev. D
76 023515

[17] He T M and Zhang J Y 2007 Chin. Phys. Lett.
24 3336

[18] Jiang K X, Ke S M, Peng D T and Feng J 2009 Chin.
Phys. Lett. 26 070401

[19] Weinhold F 1975 J. Chem. Phys. 63 2479

[20] Ruppeiner G 1979 Phys. Rev. A 20 1608

[21] Ruppeiner G 1995 Rev. Mod. Phys. 67 605

[22] Mrugala R 1984 Physica A 125 631

Salamon P, Nulton J D and Ihrig E 1984 J. Chem. Phys.
80 436

[23] Davies P C W 1977 Proc. Roy. Soc. Lond. A 353
499

Davies P C W 1989 Class. Quant. Grav. 6 1909

[24] {\AAman J E, Bengtsson I and Pidokrajt N 2003 Gen.
Rel. Grav. 35 1733

[25] Quevedo H 2007 J. Math. Phys. 48 013506

[26] Shen J, Cai R G, Wang B, Su R K 2005 Int. J. Mod.
Phys. A 22 11

[27] Wei Y H 2008 Chin. Phys. Lett. 25 2782

[28] Gibbons G W, Horowitz G T and Townsend P K 1995
Class. Quantum Grav. 12 297

[29] Cai R G 1998 J. Korean Phys. Soc. 33 S477

[30] Quevedo H and S\'{anchez A 2008 J. High Energy
Phys. 0805 034