The lost transistor? (Makezine, 2009)
https://makezine.com/article/technology/the-lost-transistor/
点接触トランジスタの類型
The Transistor Enigma
https://web.archive.org/web/20090404052348/http://www.aethmogen.com/wri/radams/tenigma1/toc.shtml
“THE ADAMS CRYSTAL AMPLIFIER
The Adams Crystal Amplifier was invented, 1933, by Robert G. Adams, at the age of thirteen years, at 418 Queen Street West, Hastings, Hawkes Bay, New Zealand, the assembly of which is depicted, as Adams described it, in the artist’s impression.”