20 February 1980 - Institutional correspondence A letter from Ricardo de la Cierva Hoces to Adolfo Suárez
Madrid, 28 June 1980 - Institutional correspondence Ricardo de la Cierva Hoces' letter to Javier Tusell
21 May 1976 - Personal correspondence Letter from Tomàs Llorens to Claude Picasso within the context of the Venice Biennale