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, 28 October 1953 - Institutional correspondence Maria Oliva Fraga's letter to Arturo Profili, dated 28 October 1953
Paris, 5 November 1953 - Institutional correspondence Maria Oliva Fraga's letter to Arturo Profili, dated 5 November 1953