First Author:   Jürgen-Peter Kretschmer Bundeskartellamt juergen.kretschmer@bundeskartellamt.bund.de   Kaiser-Friedrich-Straße 16 Bonn, 53113, Germany   +49-228-9499263(Phone) +49-228-9499263(Fax) Second Author: Oliver Budzinski University of Southern Denmark obu@sam.sdu.dk   Niels Bohrs Vej 9-10 Esbjerg, 6700, Denmark   +45-6550-4159(Phone) +45-6550-1091(Fax)