New York, 6 May 1955 - Institutional correspondence A letter from W.R. Keating & Company International to R. Lerondelle
New York, 23 January 1957 - Transport documents A letter from the vice-president of W. R. Keating & Company to Willem Sandberg
Madrid, 7 and 19 January 1981 - Institutional correspondence A letter from Enrique Calduch to Javier Tusell
Madrid, 28 de abril de 2017 - Conferences and articles Politics of the myth. Picasso, Bataille and antifascism