RT Book T1 Prevention and control of collective violence / 2 Guidelines for community relations personnel JF Prevention and control of collective violence A1 Callahan, William T. A1 Knoblauch, Richard A2 Knoblauch, Richard LA Undetermined PP Washington, D.C. PB U.S. Dept. of Justice, Law Enforcement Assistance Administration YR 1973 UL https://krimdok.uni-tuebingen.de/Record/1098689224