Free electron-positron pair production in collisions of Au79+(10.8 GeV/u) with Cu29+, Ag47+ and Au79+ R. Tenzer, N. Grün and W. Scheid Eur. Phys. J. D, 11 3 (2000) 347-353 Published online: 15 September 2000 DOI: 10.1007/s100530070062