Bleg

I'm looking for a particular study--one in which students were given a piece of (false) negative information about a teacher, and then told this had been a mistake, that the bad information was about someone else. Nonetheless, when the students who had gotten the bad information were asked to evaluate the teacher, they systematically ranked him/her lower than the students who had never heard it--even though they now knew this to be false. Can anyone help? I had the study, but I can't find it, nor remember the name.