Helios 44/2 on Nikon F mount infinity focus achieved without extra glass adapter | Nikon DSLR and M42 lenses (all Nikon DSLR from 2006 onwards) | Flickr
Fixing the focus to infinity issue of the Helios 44-2 on M42 to Nikon F mount adapter - YouTube
Amazon.com : Helios 44-2 M42 Russian Lens for Nikon Cameras Not Used Like New : Electronics
Helios 44-2 on nikon FX: possible and how?: Nikon SLR Lens Talk Forum: Digital Photography Review
Helios 44–2 lens for Nikon F mount | Yeah, nah, aye
Helios-44-2 58mm F2 Lens for Zenit Adapter Sony E NEX - Etsy
HELIOS 44-2 Lens Trioplan Modified, Mount adapter for SONY NEX, Canon EOS, Nikon | eBay
MC HELIOS-44M-4 58mm 1:2 lens information and sample photos - Nikon Rumors