In the address book of Fürth from 1859, the following entry can be found: First main district - Rosenstraße 261q - Morgenthau Moritz, Manufakturwaren und Spiegelglas en gros Handlung.

In the address book of the city of Augsburg from the year 1926 the following entries can be found: Page 182  - Horkheimer Hch., sugar confectionery wholesaler,( Inh. d. Fa.: Heinr. Horkheimer ), Volkhartstr. 6/1.  -  Heinrich Horkheimer,*  Fa. (Inh.:Heinrich Horkheimer, sugar confectionery wholesaler, Mittlere Maximilianstr. B 14.; - Part IV: Page  134  - Sugar confectionery.   - a.) Wholesalers - Horkheimer H., Mittlere Maximilianstr. B 14. 

In the city address book of the city of Coburg from 1937, the following entry can be found: Kahn, Sally, merchant, Darmhandlung, Mohrenstraße 7b.

In the Regensburg address book 1903 the following entry is found: Jonas Hahn, scrap iron and broken metal en gros und en detail, Weißgerbergraben 7.

The Niedermayer brothers were owners of a private bank in Regensburg. Listed in the 1903 Regensburg address book as Bankgeschäft Josef und Leopold Niedermayer, Ludwigstraße 8.

Entry in the address book Regensburg 1903 - banking business Dr. Hugo Thalmessinger and August Strauß, cheerful Türkenstraße 1

1904 - Conversion after marriage to the Catholic Viennese actress Catharina Schwarz