Madrid, 2 December 1975 and Berkeley, California, 8 January 1976 - Institutional correspondence A letter from José Mario Armero to Herschel B. Chip, with reply
Amsterdam, 25 January 1956 - Transport documents M. Winter's letter to Robert Giron, dated 25 January 1956
Amsterdam, 25 January 1956 - Institutional correspondence M. Winter's letter to Robert Giron, dated 25 January 1956
Whitechapel Gallery, London, 14 March 2010 - Performance 119-minute circle. The International Congress at the Whitechapel Gallery