• 3 Videos, Slides, Films

• 3 Astronomy
• 2 Exploration
• 2 Outer space
• 1 Manned space flight
• 1 Mechanics
• 1 Outer space--Exploration
• 1 Sound
• 1 Sound-waves
• 1 Wave theory of light
• 1 Waves

• 3 Films Media Group
• 2 PBS (Firm)
• 1 A&E Networks (Firm)

• 3 Internet videos
• 3 Video recordings for the hearing impaired

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