“Concurrency of Social Security System in the Ibero-American Level. Rules for Determining the Appropriate Legal Instrument for Coordination of Social Security Systems”. Revista de Derecho de la Seguridad Social, Laborum, no. Extraordinaria nº 7, Dec. 2024, pp. 205-16, https://revista.laborum.es/index.php/revsegsoc/article/view/1039.