Balsells, Angels, et al. „Needs Analysis for a Parental Guidance Program for Biological Family: Spain’s Current Situation”. Revista de Cercetare si Interventie Sociala, vol. 34, septembrie 2011, pp. 21-37, https://www.rcis.ro/journal/article/view/376-needs-analysis-for-a-parental-guidance-program-for.