Oputakon, torēningu Eibun manyuaru (Nihongo yaku tsuki)
Subtitle: Oputakon 20-shūnen kinen
By: Shintani Mamoru, Igarashi Fumiko, Takahashi Rumi hencho
Edition: Dai 1-han
Publisher: Nihon Oputakon Iinkai
Published: 1991
Place of publication: Tōkyō
Language: jpn
Number of pages: 270
Other titles: Optacon training manual for English reading (with Japanese translation)