New York, 6 May 1955 - Institutional correspondence A letter from W.R. Keating & Company International to R. Lerondelle
New York, 23 January 1957 - Transport documents A letter from the vice-president of W. R. Keating & Company to Willem Sandberg
ca. 1952–1956 - Internal museum documents Publicity report for the exhibition Studies for Guernica by Normal University, Illinois, addressed to the Travelling Exhibitions Department at the Museum of Modern Art, New York
New York, 29 March 1972 - Photograph View of the permanent collection from New York's Museum of Modern Art