Valuable material on transistor technology. - Title: Transistor Germanium Diode - Publisher: Tokyo Tsushin Kogyo Co., Ltd. Thank you for viewing. This is a book/magazine published in Showa 31 (1956). Due to long-term storage at home, it has aged over time. I will sell it to those who are interested in transistors, etc., as reference material. Returns are not accepted after purchase. Please understand the above before purchasing.