Published by:
The Royal Swedish Academy of Sciences ©, Information Department, Box 50005, S-104 05 Stockholm, Sweden, Tel. +46 8 673 95 00

Editors:
Solgerd Björn-Rasmussen, Margareta Wiberg Roland, The Royal Swedish Academy of Sciences

Author:
Dr Erik Johansson, Department of Physics, Stockholm University, Sweden

Layout and illustrations:
Kjell Lundin, Explicare, Sweden

Printed by:
Tryckindustri, Sweden

Web Adapted Version:
Nobelprize.org

Every effort has been made by the publisher to credit organizations and individuals with regard to the supply of photographs and illustrations. The publishers apologize for any omissions which will be corrected in future editions.