Hanf, Theodor, 1936-, Weiland, Heribert, 1942-, Vierdag, Gerda, Schlemmer, Lawrence 1936-2011, Hampel, Rainer, Krupp, Burkhard, Richardson, John, Orkin, Mark. Rex Collings; 1981. South Africa, the prospects of peaceful change: an empirical enquiry into the possibility of democratic conflict regulation.