Roxbury, 22 November 1955 - Institutional correspondence Alexander Calder's letter to Willem Sandberg, dated 22 November 1955
Roxbury, 12 January 1956 - Institutional correspondence Alexander Calder's letter to Willem Sandberg, dated 12 January 1956
ca. 1952–1956 - Internal museum documents Publicity report for the exhibition Studies for Guernica by the School of Fine and Applied Arts, Columbus, Ohio, addressed to the Travelling Exhibitions Department at the Museum of Modern Art, New York