Costa, Jorge Lopes da, et al. “The Impact of Patients in ‘extreme vulnerability’ on Their Primary Caregivers: A Multidimensional Perspective”. Revista Kairós-Gerontologia, vol. 17, no. 1, Mar. 2014, pp. 27-43, doi:10.23925/2176-901X.2014v17i1p27-43.