Zapata-Posada, Johanna Jazmín, et al. “Grandmothers Earlier Than Expected: Women Life Changes, Involvement in Grandchildren Rising and Intergenerational Relationships”. Prospectiva. Revista De Trabajo Social E Intervención Social, no. 22, Oct. 2016, pp. 117-40, https://doi.org/10.25100/prts.v0i22.1239.