Copenhagen, 31 October 1956 - Institutional correspondence Lars Rostrup Boyesen's letter to Pablo Picasso
Copenhagen, 31 October 1956 - Institutional correspondence Lars Rostrup Boyesen's letter to Daniel-Henry Kahnweiler
Copenhagen, 31 October 1956 - Institutional correspondence Lars Rostrup Boyesen's letter to the Museum of Modern Art, New York
1969 - Internal institutional documents A loan form for the replica Guernica tapestry at the Hudson River Museum
<em>The New York Times</em>, New York, September 28, 1969, section D, 35 - Article “Keeping Art On The Streets”