Matematikundervisningen og samfundet. Virum: MATEMATIK, n.d. [1980]. Scanned camera-ready manuscript.

Bronze Age Formal Science?, pp. 81-102 in Benedikt Löwe, Volker Peckhaus & Thoralf Räsch (eds), Foundations of the Formal Sciences IV. The History of the Concept of the Formal Sciences. (Studies in Logic, 3). London: College Publications, 2006. Preprint. (Last pages about didactics).


[Review of Danny Bernard Martin, Mathematics Success and Failure among African-American Youth. The Roles of Sociohistorical Context, Community Forces, School Influence, and Individual Agency. (Studies in Mathematical Thinking and Learning). Mahwah, N.J., & London: Lawrence Erlbaum, 2000]. Zentralblatt für Mathematik und ihre Grenzgebiete 0961.00006.



[Review of L. Streefland (ed.), The Legacy of Hans Freudenthal. Dordrecht etc.: Kluwer, 1993. [Identical with Educational Studies in Mathematics 25:12 (1993)]. Zentralblatt für Mathematik und ihre Grenzgebiete 0792.01035.