Numerical Renormalization Group at Criticality
  We apply a recently developed numerical renormalization group, the corner-transfer-matrix renormalization group (CTMRG), to 2D classical lattice models at their critical temperatures. It is shown that the combination of CTMRG and the finite-size scaling analysis gives two independent critical exponents. 
T. Nishino, K. Okunishi, and M. Kikuchi