We have searched for D-0-(D) over bar (0) mixing in D*(+)->pi D-+(0) decays with D-0 -> K-(*())e nu in a sample of e(+)e(-)-> c (c) over bar events produced near 10.58 GeV. The charge of the slow pion from charged D* decay tags the charm flavor at production, and it is required to be consistent with the flavor of a fully reconstructed second charm decay in the same event. We observe 3 mixed candidates compared to 2.85 background events expected from simulation. We ascribe a 50% systematic uncertainty to this expected background rate. We find a central value for the mixing rate of 0.4x10(-4). Using a frequentist method, we set corresponding 68% and 90% confidence intervals at (-5.6,7.4)x10(-4) and (-13,12)x10(-4), respectively.
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