<unk> <unk> <unk> <unk> <unk>  1978: State Bank of Vietnam (Ngân hàng Nhà nước Việt Nam) introduced notes in denominations of 5 hào, 1, 5, 10, 20, and 50 đồng dated 1976. ️<unk>️<unk>️<unk>️<unk>️<unk> <unk> <unk> <unk> <unk> <unk> <unk>  Question: When did the State Bank of Vietnam add 2 and 10 dong notes?
1980 <unk> <unk> <unk> <unk>