An output feedback design technique is presented. The design technique achieves semiglobal practical stabilization for a class of nonminimum-phase nonlinear systems, subject to parameter uncertainties. This work is an extension of the result by Isidori in 2000. It provides a constructive controller design method for an auxiliary system, whose existence is crucial but is only assumed in Isidori's work. The control design technique is is used to regulate the benchmark van de Vusse reactor. Simulation results demonstrate satisfactory controller performance.