Helios 44-2 | Helios 44-2 is well known lens. It brings a lot of character and swirly bokeh to an image. Please check up how this lens behaves on different aperture...
Creating swirly bokeh with the Helios 44-2 lens
Finding Fall + Mini Helios 44-2 Lens Review — Zak Koltun
Canon M100 and Helios 44-2 lens with an adapter ?: Adapted Lens Talk Forum: Digital Photography Review