Stockholm, 23 October 1956 - Institutional correspondence Ernesto de Zulueta's letter to Alberto Martín-Artajo Álvarez
Tokyo, 20 November 1962 - Institutional correspondence Akira Jin's letter to Pablo Picasso, dated 20 November 1962
Tokyo, 31 August 1962 - Institutional correspondence Akira Jin's letter to Carol K. Uht, dated 31 August 1962
Tokyo, 21 November 1962 - Institutional correspondence Akira Jin's letter to Carol K. Uht, dated 21 November 1962
Tokyo, 1 April 1963 - Institutional correspondence Akira Jin's letter to Pablo Picasso, dated 1 April 1963