Inteview by Betty van Garrel and Rem Koolhaas for weekly magazine Haagse Post on the occasion of the presentation of his works in the Dutch Paviljoen at the Venice Biennial, 1966
A television course with accompanying course book: Openbaar Kunstbezit tv. Constant | Schilderijen, constructies, Nieuw Babylon is part of the episode of July 7, 1965 in the third year.
Small news item in Leidsch Dagblad about Constants demand to have the painting Barricade returned to him by the Stedelijk Museum Amsterdam, April 21, 1964.