MacLeod S, Tkatch R, Kraemer S, Fellows A, McGinn M, Schaeffer J, Yeh CS. The impact of COVID-19 on informal caregivers in the US. Int J Aging Res. 2021 Jan;4(87).
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.