|Yahō A on a Semi Pearl. From the 1951 camera annual by Nihon Camera. (Image rights)|
Miyama Shōkai (みやま商会, meaning Miyama Trading Company) was a Japanese company in the late 1940s and early 1950s, about which almost nothing is known. Its name certainly implies that it was only a distributor. It is said that it sold the Yahō accessory rangefinder from 1949 for the Semi Pearl.
- Sold the Yahō: Noma, p.65.
- Nihon Camera special issue Kamera Nenkan 1951-nenban (カメラ年鑑1951年版, Camera annual, 1951 edition). October 1950. "Shuyō kokusan kamera akusesarī" (主要国産カメラアクセサリー, Main Japanese camera accessories). P.49. (Contains a picture of the Yahō, but does not mention Miyama.)
- Noma Toshio (野間俊夫). Kyorikei-tsuki kamera no henpo (距離計付きカメラの変遷, Evolution of rangefinder cameras). Gendai Kamera Shinsho (現代カメラ新書) 65. Tokyo: Asahi Sonorama, 1979. No ISBN number. Pp.64–5. (On the Yahō rangefinder.)