• 20 History
• 19 Power (Social sciences)
• 18 Commerce
• 18 Territorial expansion
• 4 Indians of North America
• 3 African Americans
• 3 Immigrants
• 3 Imperialism
• 3 Labor
• 3 Politics and government
• 2 Emigration and immigration
• 2 Industrialization
• 1 American literature
• 1 Christianity
• 1 Civil law
• 1 Courts
• 1 Criminal law
• 1 Culture conflict
• 1 Democracy
• 1 Deviant behavior
• 1 Ethnicity
• 1 Gold miners
• 1 Harlan, John M. (John Marshall), 1899-1971
• 1 Industries

• 20 Films Media Group
• 20 Films for the Humanities & Sciences (Firm)
• 7 Public Broadcasting Service (U.S.)
• 5 KERA Dallas/Ft. Worth (Television station)
• 4 Infobase
• 3 A&E Television Networks, LLC
• 1 ABC News Productions
• 1 MacNeil/Lehrer Productions
• 1 Marshall University
• 1 Sideways Film
• 1 Spangler, Lynnn C

• 20 English

• 20 United States
• 2 West (U.S.)
• 1 New York (N.Y.)
• 1 Pleasant Hill (Ky.)
• 1 San Antonio, Texas

• 20 Educational films
• 20 Internet videos
• 5 Video recordings for the hearing impaired

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