[1] Buckley J R, Wise F W, Ilday F \"O and Sosnowski T 2005 CLEO, CTuK4

[2] Anderson D, Desaix M, Lisak M and Quiroga-Teixeiro M L 1992
Opt. Soc. Am. B 9 1358

[3] Nelson L E, Fleischer S B, Lenz G and Ippen E P 1996 Opt.
Lett. 21 1759

[4] Fermann M E, Kruglov V I, Thomsen B C, Dudley J M and Harvey
J D 2000 Phys. Rev. Lett. 84 6010

[5] Kruglov V I, Peacock A C, Harvey J D and Dudley J M 2002
Opt. Soc. Am. B 19 461

[6] Ilday F, Buckley J R, Clark W G and Wise F W 2004 Phys.
Rev. Lett. 92 213902-1

[7] Buckley J R, Wise F W, Ilday F \"O and Sosnowski T 2005
Opt. Lett. 30 1888

[8] Ruehl A, Prochnow O, Wandt D, Kracht D, Burgoyne B, Godbout N and
Lacroix S 2006 Opt. Lett. 31 2734

[9] Kalosha V P, Chen L and Bao X Y 2006 Opt. Exp. 14 4935

[10] Latkin A and Turitsyn S 2006 ICTON 259

[11] Anderson D, Desaix M, Karlsson M, Lisak M and Quiroga-Teixeiro M L
1993 Opt. Soc. Am. B 10 1185