"K.R. Thurber,Takashi Imai,Takashi Saito,M. Azuma,M. Takano,F.C. Chou","63Cu NQR Evidence of Dimensional Crossover to Anisotropic 2D Regime in S=1/2 Three-Leg Ladder Sr2Cu3O5",,"Phys. Rev. Lett.",,"Vol. 84","No. 3","pp. 558-561",2000,