Pars, 9 February 1955 - Institutional correspondence Pablo Picasso's letter to Alfred H. Barr Jr., dated 9 February 1955
New York, 6 August 1973 - Institutional correspondence A letter from Betsy Jones to Daniel-Henry Kahnweiler
New York, 18 September 1964 - Institutional correspondence A letter from Betsy Jones to Alfred H. Barr Jr., dated 18 September 1964