- Draft versions of unknown lectures
- Die Entwicklung der modernen Baukunst in Holland: Vergangenheit, Gegenwart, Zukunft, 1923
- Opening exhibition Rietveld, 1934
- Opening exhibition The Hague builds up, 1946
- What is monumental, 1949
- White Village 25 years, 1949
- Dudok 65 years, 1949
- BIM building at Art Critics Symposium, 1951
- Radio conversation West-deutsche Rundfunk, 1951
- Radio conversation, February 25, 1951
- Opening exhibition Alex de Haas, 1953
- Opening exhibition Building in the Netherlands, 1954
- Opening Mondrian exhibition, 1955
- The Dam monument, 1956
- Opening exhibition L.O. Wenkenbach, 1959
- Television appearance, the importance of the Stock Exchange, 1960
- Recording of gramophone record, 1961