秘密スイッチX

First Japanese edition of this selection. {{Tr|{{A|Kenji Matsutani}}}} (松谷健二). This entry is for the initial printing. Data from <a href="https://ameqlist.com/0ha/haya/rhodan1.htm">ameqlist.com</a> and the National Diet Library. Number 12 in the series 宇宙英雄ローダン (Uchuu hideo Rōdan) -- Space Hero Rhodan. Ameqlist notes the inclusion of an essay by 松谷健二 (Kenji Matsutani, the translator) but doesn't give a title.