1. and , Notes on constructive set theory. Report No. 40, Institut Mittag-Leffler, Royal Swedish Academy of Sciences, 2001.
2. Foundations of Constructive Mathematics: Metamathematical Studies. Ergebnisse der Mathematik und ihrer Grenzgebiete, 3. Folge, 6 (Springer-Verlag, 1985).
3. Foundations of Constructive Analysis (McGraw-Hill, 1967).
4. and , Constructive Analysis. Grundlehren der Mathematischen Wissenschaften 279 (Springer-Verlag, 1985).
5. The set w and its related pre-apartness on an a-frame. Preprint, University of Canterbury, 2007.