Richard Marx died in Camp Westerbork at age 48 on 27 August 1942. He was buried at the Jewish cemetery in Assen on 30 August 1942.
Jewish Historical Museum, Documents collection, inv.nr 3397; Death register of the Jewish community Assen
The funeral records at the Jewish cemetery in Assen reveal that Richard Marx was buried there.
This person is commemorated on a memorial in Assen. More information on this memorial can be found (in Dutch) on the website of the Nationaal Comité 4 en 5 mei.