FBI: Freedom of Information Act: Arthur Flegenheimer Bureau files on the New York bootlegger and numbers racketeer known as Dutch Schultz. http://foia.fbi.gov/foiaindex/flegenheimer.htm
FBI: Freedom of Information Act: Benjamin 'Bugsy' Siegel Bureau files on New York/California/Las Vegas racketeer Siegel contain 2,421 pages. http://foia.fbi.gov/foiaindex/siege.htm
Wikipedia: Bugsy Siegel Biography of the gangster. Topics include Siegel's underworld business ventures in Los Angeles and Las Vegas (Flamingo Hotel), and his 1947 assassination. http://en.wikipedia.org/wiki/Bugsy_Siegel
Wikipedia: Louis Buchalter Biography of the New York garment industry racketeer and Murder Inc. boss who was executed in the electric chair in 1944. http://en.wikipedia.org/wiki/Louis_Buchalter