Date/place of birth identified in Siegfried Wolf. Juden in Thüringen 1933-1945: Biographische Daten. (2000), vol 2 (unpaginated)
Identified as daughter of Sara and Jakob Spiegel in Wolf
In 1936, Bertha Spiegel left Germany, sailing from Hamburg on 8 April 1936 for New York City. [Source: New York, Passenger Lists, 1820-1957 [database on-line]. Provo, UT, USA: Ancestry.com Operations, Inc., 2010].
identified as wife of Joseph Maier, with date of marriage, in New York, Naturalization Records, 1882-1944 (Ancestry.com)
Death date/place in U.S., Social Security Death Index, 1935-2014 [database on-line]. Provo, UT, USA: Ancestry.com Operations Inc, 2011.