Denki ryōkin chōsa
Series: Shiryō -- dai 72-gō; Shiryō (Sangyō Keizai Kenkyūjo) -- dai 72-gō.
Publisher: Sangyō Keizai Kenkyūjo
Published: 1941
Place of publication: Tōkyō
Language: jpn
Number of pages: 81
Notes: Issued as confidential document.