Digital audio recording during video shooting: Nikon High Definition DSLR
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How to set-up and external mic on a DSLR - YouTube
Amazon.com: iShoot DC/DV Dedicated Microphone Mono MIC with 3.5mm Audio Plug Compatible with Canon Nikon Digital Camera & Video Camcorder with 3.5mm Mic Jack, ±30 ° Tilt Angle Adjustable : Electronics
Nikon D750 DSLR Camera with 24-120mm Lens and Microphone Kit