Arana A, Cuchi T, Arellano F. Strengthening EU pharmacovigilance. European pharmaceutical contractor. European pharmaceutical contracto: EPC. 2009;44-5.
Hartman M, Bolton E, Fehnel SE. Accounting for age differences on the Wisconsin Card Sorting Test: decreased working memory, not inflexibility. Psychol Aging. 2001 Sep 1;16(3):385-99.