The chief executive of Deutsche Bank’s (DBKGn.DE) retail arm Postbank (DPBGn.DE) strongly advocates having Deutsche sell a large portion of Postbank’s shares on the stock market rather than to another bank, a German magazine reported on Saturday. Weekly WirtschaftsWoche said selling the shares on the market would be much easier than selling them to a competitor such as Spain’s Santander (SAN.MC) or splitting off Deutsche Bank’s entire retail banking operation.