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
New York, 8 May 1968 - Institutional correspondence Antonio Serrano's letter to Fernando María Castiella