Peter Keller, the author's son, gave the United States Holocaust Memorial Museum Archives copies of the letters in Aug. 1994.

http://lod.ehri-project-test.eu/acquisitions/us-005578-irn504346-eng-irn504346_eng an entity of type: Activity

Peter Keller, the author's son, gave the United States Holocaust Memorial Museum Archives copies of the letters in Aug. 1994. 
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