|Camera industry in Berlin|
|Agfa | Amigo | Astro Berlin | Bermpohl | B W | Foth | Goerz | Grass & Worff | Plasmat | Rudolph | Rüdersdorf | Schulze & Billerbeck|
Rüdersdorf was a German optical company located in Berlin in the 1920s, which used the trademark Rüo for a number of lenses. Its lenses are marked "Opt-Werke Rüdersdorf-Berlin".
- Yazawa Seiichirō (矢沢征一郎). "Raika-yō kawaridane kōkan-renzu" (ライカ用変り種交換レンズ, A singular interchangeable lens in Leica mount). In Camera Collectors' News no.46 (April 1981). Nishinomiya: Camera Collectors News-sha. Pp.5–8.