Stockholm, 23 October 1956 - Institutional correspondence Ernesto de Zulueta's letter to Alberto Martín-Artajo Álvarez
Paris, 3 November 1980 - Institutional correspondence Dominique Bozo's letter to Josep Lluís Sert, dated 3 November 1980
Paris, 23 December 1980 - Institutional correspondence Dominique Bozo's letter to Josep Lluís Sert, dated 23 December 1980