Stockholm, 23 October 1956 - Institutional correspondence A letter from Bo Wennberg and K. G. Hulten to Pablo Picasso
Madrid, 30 March 1988 - Internal institutional documents A letter from the director-general of Fine Arts to the Cabinet of Spain's Ministry of Culture
Madrid, 14 September 1981 - Institutional correspondence Official notice from the Management Board of Fine Arts, Archives and Museums to José Manuel Pita Andrade