|Founded 1929 by John Dopyera, Los Angeles. Now owned by Gibson.
1974 Dobro Catalog http://www.resoguit.com/catalog.html
Dobro also made guitars under the following brand names:
Norwood Chimes, Broman, Angelus, Montgomery Ward, and Penetro. After World War II – Hound Dog, DB Original, and Replica 66. [Source: The Hawaiian Steel Guitar and Its Great Hawaiian Musicians By Lorene Ruymar ]
Dobro reference books
Dobro Guitars – A Pictorial History
Image 1981 Dobro serial number eBay: