Mr. Nguyễn Bá Đạm (middle), the oldest collector in HanoiMr. Howard A. Daniel III (middle), the author of many important books on Vietnamese NumismaticsBook cover: Howard A. Daniel III, "Democratic Republic of Vietnam coin and currency", Trẻ Publishing House, 2016Collectors attending the announcement ceremony of the "History of the Vietnam Bank Foundation and Development" book and inauguration of the Vietnamese currency galleryVietnam 5000 Dong Cong Phieu 1964Vietnam 10000 Dong Cong Phieu 1964 and trial printsUnissued Vietnam 500 DongSerial number printing device 1946-1947(*)
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art-hanoi.com: Looks rather like a Soviet arithmometer (mechanical calculator) "FELIX M" [Феликс М] :)