Gradinarsky, Lubomir P.
Haas, RĂ¼diger
Elgered, Gunnar
Johansson, Jan M.
Article History
Received: 25 December 1999
Revised: 9 June 2000
Accepted: 21 June 2000
First Online: 24 June 2014
Free to read: This content has been made available to all.