Lensfinder.com - Ultra Rare Nikkor 6mm f/5.6. Only a few hundred of these lenses exist. This lens has a 220 degree field of view for Full Frame 24x36mm sensors. Made in Japan
How can nikkor 6mm f/2.8 see behind itself?: Open Talk Forum: Digital Photography Review
The remarkable Nikkor 6mm f/2.8 Fisheye - Japan Camera Hunter
Not for the frugal fisheye photographer: Rare Nikon 6mm f/2.8 Ai-S lens available on eBay for around $85k
Deal of the day: Nikon Fisheye-Nikkor 6mm f/5.6 circular fisheye lens for $5,999 - Nikon Rumors
Rare Lens] $160,000 Nikkor 6mm 2.8 Fisheye Can See Behind You | Fstoppers
Uber-Rare Nikon 6mm Fisheye Lens on eBay Can See Behind Itself | PetaPixel
Lens pr0n: The Nikkor 6mm f/2.8 fisheye monster | TechCrunch
Nikkor 6mm f/2.8 Fisheye Nikkor lens
This Uber-Rare Nikon 6mm f2.8 Fisheye Lens Can See Behind Itself - The Phoblographer
Nikon Fisheye Nikkor 6mm f/2.8 Lens | modern design by moderndesign.org
Deal of the day: Nikon Fisheye-Nikkor 6mm f/5.6 circular fisheye lens for $5,999 - Nikon Rumors
How can nikkor 6mm f/2.8 see behind itself?: Open Talk Forum: Digital Photography Review
Nikon 6mm f2.8 220° fisheye - Media And Arts - Newschoolers.com
This Massive Nikon Fisheye-Nikkor 6mm f/2.8 Lens Will Cost You $161,000 - TechEBlog
Huge 11-Pound Nikon 6mm ƒ2.8 Fisheye Lens Goes On Sale | Cult of Mac