Stockholm, 23 October 1956 - Institutional correspondence Ernesto de Zulueta's letter to Alberto Martín-Artajo Álvarez
Paris, 28 October 1953 - Institutional correspondence Maria Oliva Fraga's letter to Arturo Profili, dated 28 October 1953
Paris, 5 November 1953 - Institutional correspondence Maria Oliva Fraga's letter to Arturo Profili, dated 5 November 1953