London, 18 April 1980 - Institutional correspondence Nicholas Serota's letter to Roland Penrose, dated 18 April 1980
London, 1 May 1980 - Institutional correspondence Nicholas Serota's letter to Roland Penrose, dated 1 May 1980
ca. 1952–1957 - Internal museum documents Publicity report for the exhibition Studies for Guernica by the Museum of Cranbrook, New Jersey, addressed to the Travelling Exhibitions Department at the Museum of Modern Art, New York