Javier Tusell, director-general of Fine Arts, writes to Claude Picasso, the painter's son, with questions over the installation of Guernica in the Casón del Buen Retiro. He also reiterates his gratitude for his willingness to participate in the negotiation process and the transfer of the painting, as well as having agreed to form part of the Honorary Committee of the Picasso Centenary.
España. Ministerio de Educación, Cultura y Deporte. Archivo Histórico Nacional