School of Computing, Staffordshire University, Stafford, ST18 0DG
email: A.J.Dix@soc.staffs.ac.uk
url: http://www.hcibook.com/alan/
School of Computer Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT
email: R.Beale@cs.bham.ac.uk
url: http://www.cs.bham.ac.uk/~rxb/