28 February 1974 - Press release and communication The artist Tony Shafrazi has freed Guernica from its chains of ownership and has returned its revolutionary nature
New York, 4 May 1950 - Institutional correspondence Joseph Schwartz's letter to the Museum of Modern Art, New York
ca. 1952–1957 - Internal museum documents Publicity report for the exhibition Studies for Guernica by the Kansas State Teachers College, Pittsburg, addressed to the Travelling Exhibitions Department at the Museum of Modern Art, New York