Flushing, New York, 23 May 1939 - Institutional correspondence Simon Guggenheim's and Dana C. Backus's form letter to ask for donations
<em>El País</em>, January 21, 2016 - Article “El fiasco de la Bienal de Arte de Sevilla acaba en condena” (The fiasco of the Art Biennial of Seville ends up with a sentence)