Haas, RĂ¼diger
Gueguen, Erwan
Scherneck, Hans-Georg
Nothnagel, Axel
Campbell, James
Article History
Received: 22 December 1999
Revised: 18 May 2000
Accepted: 19 May 2000
First Online: 24 June 2014
Free to read: This content has been made available to all.