Paris, 10 February 1955 - Institutional correspondence Daniel-Henry Kahnweiler's letter to Alfred H. Barr Jr., dated 10 February 1955
Mainz, 2 May 1956 - Institutional correspondence J. Mougin's letter to François Mathey, dated 2 May 1956
Paris, 14 March 1956 - Personal correspondence Daniel-Henry Kahnweiler's letter to Pablo Picasso, dated 14 March 1956