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Kornell N, Metcalfe J.Kornell N, et al. Among authors: metcalfe j.J Exp Psychol Learn Mem Cogn. 2006 May;32(3):609-22. doi: 10.1037/0278-7393.32.3.609.J Exp Psychol Learn Mem Cogn. 2006.PMID: 16719670