D I Stewart Editor

C. M. Campbell is Honorary Reader in the School of Mathematics and Statistics at the University of St Andrews. M. R. Quick is Senior Lecturer in the School of Mathematics and Statistics at the University of St Andrews. E. F. Robertson is Emeritus Professor in the School of Mathematics and Statistics at the University of St Andrews. C. M. Roney-Dougal is Professor of Pure Mathematics in the School of Mathematics and Statistics at the University of St Andrews. D. I. Stewart is Reader in the Department of Mathematics at the University of Manchester.