Madrid, 2 December 1975 and Berkeley, California, 8 January 1976 - Institutional correspondence A letter from José Mario Armero to Herschel B. Chip, with reply
Paris, 14 November 1964 - Institutional correspondence A letter from Le Groupment des Anciens Etudiantes de l'Université et des Écoles Supérieures de Budapest, etudiant de France [sic], to Pablo Picasso