SIERRA GARCÍA, P. Attachment : Research and development. Acción Psicológica, [S. l.], v. 8, n. 2, p. 5–7, 2012. DOI: 10.5944/ap.8.2.186. Disponível em: https://revistas.uned.es/index.php/accionpsicologica/article/view/186. Acesso em: 4 feb. 2023.