The record of the Digital Monument to the Jewish Community in the Netherlands http://www.joodsmonument.nl/person.php?thg_id=1007.23031&lang=en confirms that Maria Loewenberg-Blumenthal, married to Fritz Siegfried Loewenberg, was born in Kowno on 28th September 1902 and died in Auschwitz, 7th September 1942.

The Yad Vashem record is as follows:
 
Full Record Details for Loewenberg Maria
 
Source
    
In Memoriam - Nederlandse oorlogsslachtoffers, Nederlandse Oorlogsgravenstichting (Dutch War Victims Authority), `s-Gravenhage (courtesy of the Association of Yad Vashem Friends in Netherlands, Amsterdam)
Last Name
    
LOEWENBERG
First Name
    
MARIA
Maiden Name
    
BLUMENTHAL
Date of Birth
    
28/9/1902
Place of Birth
    
KOWNO,KAUNAS,LITHUANIA
Place of Death
    
AUSCHWITZ,CAMP
Date of Death
    
7-9-1942
Type of Material
    
list of deportation from the Netherlands
Language
    
DUTCH

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