Anders / Other
apparaten
(my small collection of calculating and cryptographic devices, texts in Dutch only)
Klokken / Clocks
Links
The Mathematics Genealogy Project
(my mathematical ancestry: Robert Tijdeman - Jan Popken - Johannes van der Corput - Jan Cornelis Kluyver - ???)
The Erdös Number Project
(my Erdös number is 2, see
the
official data)
The Mathematical Fiction Homepage