Institut für Wissenschaftsgeschichte, Georg-August-Universität Göttingen, Papendiek 16, 37073 Göttingen, Germany; dwuensc(at)gwdg.de; see also: http://www.theodorkaluza.de
Received 13 April 2003, revised 5 September 2003,
accepted 7 September 2003 by F. W. Hehl
(approx. 33 pages)
Faculty of Physics, University of Craiova, 13 A. I. Cuza Str., Craiova 200585, Romania; bizdadea(at)central.ucv.ro
Received 6 January 2003, revised 24 April 2003,
accepted 12 August 2003 by K. Fredenhagen
(approx. 30 pages)