The WTO and Reciprocal Preferential Trading Agreements 2007 HKS Authors See citation below for complete author information. Lawrence H. Summers Frank and Denie Weil Director of the Mossavar-Rahmani Center for Business and Government Charles W. Eliot University Professor Citation Summers, Lawrence H. "Regionalism and the World Trading System." The WTO and Reciprocal Preferential Trading Agreements. Ed. Caroline Freund. Edward Elgar Publishing, 2007, 421-427.