London, 9 July 1938 - Personal correspondence E. L. T. Mesens' letter to Roland Penrose, dated 9 July 1938
London, 15 September 1938 - Personal correspondence E. L. T. Mesens' letter to Roland Penrose, dated 15 September 1938
London, 20 August 1938 - Personal correspondence E. L. T. Mesens' letter to Roland Penrose, dated 20 August 1938
London, 31 August 1938 - Personal correspondence E. L. T. Mesens' letter to Roland Penrose, dated 31 August 1938
<em>The New York Times</em>, New York, February 5, 2003, 27 - Article Maureen Dowd, “Powell Without Picasso”