National Music Museum (NMM) - The Hohner harmonica company (Germany) called this double harmonica the "Up to Date Siamese Twins model." Made about 1904, this conjoined instrument features two tremolo harmonicas bound
Hohner Mini Harmonica Key of C 38C includes Free USA Shipping – RockinRonsMusic
File:Harmonika Hohner.jpg - Wikimedia Commons
Deutsches Harmonikamuseum (Trossingen) - All You Need to Know BEFORE You Go
Industrial Espionage and Cutthroat Competition Fueled the Rise of the Humble Harmonica | History| Smithsonian Magazine