We report quantum Hall experiments on the plateau-insulator transition in a low mobility In_{.53} Ga_{.47} As/InP heterostructure. The data for the longitudinal resistance rho_{xx} follow an exponential law and we extract a critical exponent kappa= .55 pm .05 which is slightly different from the established value kappa = .42 pm .04 for the plateau transitions. Upon correction for inhomogeneity effects, which cause the critical conductance sigma_{xx}^* to depend marginally on temperature, our data indicate that the plateau-plateau and plateau- insulator transitions are in the same universality class.
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