New York, 10 February 1956 - Institutional correspondence A letter from Louise A. Boyer to Petro (Nelly) Van Doesburg
Stockholm, 1956 - Photograph Photographs of the installation and exhibition of Guernica, avec 60 études at the Nationalmuseum, Stockholm
October - December 1956 - Photograph Photograph of the installation of the exhibition Guernica, avec 60 études at the Nationalmuseum, Stockholm
