ข้อมูลทรัพยากร

เนื้อหาย่อ : 1. Silent Sound 11 2. How It All Began 15 3. Sounds Unlimited 21 4. Quiet Noise 27 5. Night Hunter 32 6. Radar-Electronic Detective 37 7. Echoes of the Deep 43 8. Do Birds Fly Blind? 47 9. Ocean Obstacle Course 53 10. Ultrasonics: Today and Tomorrow 61