Madrid, 5 November 1980 - Institutional correspondence A letter from Íñigo Cavero to Blanche de Philip P. Weisberg (Blanche Mahler)
ca. 1981 - Manuscript Comments on the declarations of Blanche Mahler regarding the arrival of Guernica to New York
New York, 10 July 1939 - Institutional correspondence Blanche Mahler's letter to Grace L. McCann Morley
San Francisco, 1 August 1939 - Institutional correspondence Grace L. McCann Morley's letter to Blanche Mahler
2 May 1939 - Internal institutional documents A draft text for the invitation to the exhibition Picasso's Guernica at the Valentine Gallery, New York