
http://www.google.com/patents?id=bIszAA ... m+silencer
http://www.google.com/patents?id=wZlUAA ... m+silencer
http://www.google.com/patents?id=wJlUAA ... m+silencer
http://www.google.com/patents?id=kgguAA ... r#PPA66,M1
http://www.google.com/patents?id=HWEdAA ... er#PPP2,M1