Madrid, 17 December 1936 - Institutional correspondence Antonio Rodríguez Morey's, Manuel Azaña's and Jesús Hernández Tomás's letter to Pablo Picasso
Madrid, 26 September 1936 - Internal institutional documents Certificate of appointment for Pablo Picasso as director of the Museo Nacional del Prado
New York: Praeger Publishers Inc., 1973 - Essay Six Years: The Dematerialization of the Art Object from 1966 to 1972