Madrid, 21 February 1969 - Institutional correspondence Florentino Pérez-Embid's letter to Joaquín de la Fuente
New York, 19 May 1980 - Institutional correspondence William Rubin's letter to Rafael Fernández Quintanilla, dated 19 May 1980
New York, 17 June 1980 - Institutional correspondence William Rubin's letter to Rafael Fernández Quintanilla, dated 17 June 1980
New York, 20 March 1980 - Internal institutional documents An agreement to deliver Guernica to the Spanish government