• 8 Videos, Slides, Films

• 6 Social aspects
• 4 Technology
• 1 Air conditioning
• 1 Collective memory
• 1 Communications
• 1 Digital preservation
• 1 Drinking water
• 1 Electric lighting
• 1 Engineering mathematics
• 1 Glass
• 1 Inventions
• 1 Lighting
• 1 Public health
• 1 Recording and reproducing
• 1 Refrigeration and refrigerating machinery
• 1 Sanitation
• 1 Science
• 1 Sociology
• 1 Sound
• 1 Time measurements
• 1 World War, 1939-1945

• 8 Films Media Group
• 6 Public Broadcasting Service (U.S.)
• 1 BBC Worldwide Ltd
• 1 Films for the Humanities & Sciences (Firm)
• 1 NPO/Netherlands Public Broadcast

• 8 English

• 1 Europe
• 1 Historic preservation
• 1 United States

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