Decay of correlations for non H\"{o}lderian dynamics. A coupling   approach
  We present an upper bound on the mixing rate of the equilibrium state of a dynamical systems defined by the one-sided shift and a non H\"{o}lder potential of summable variations. The bound follows from an estimation of the relaxation speed of chains with complete connections with summable decay, which is obtained via a explicit coupling between pairs of chains with different histories. 
Xavier Bressaud, Roberto Fern\'andez and Antonio Galves