University of Warwick | Mathematics Education Research Centre | Personal Site (davidtall.com)
Graphic Calculus Software | GraphicCalculus.co.uk
PME Home Page | PME 26 | PME 27
Photographs from PME 25 in Utrecht | Photographs from PME 26 in Norwich
Ask ERIC Eric Database of publications, including research papers
Other useful links:
CHEST software prices for staff and students
Educational Software Orders from Pugh Computers Ltd (sometimes slow in responding to e-mail!)
Book Brain for cheapest UK net quotes for books.
Allwhois.com to find out who is the owner of any web address.