DVD Identifier says:
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Unique Disc Identifier: [DVD + R DL: RICOHJPN-D01-067]
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Disc & Book Type: [DVD + R DL] - [DVD-ROM]
Manufacturer Name: [Ricoh Co. Ltd.]
Manufacturer ID: [RICOHJPN]
Media Type ID: [D01]
Product Revision: [067]
Blank Disc Capacity: [4,173,824 Sectors = 8.55 GB (7.96 GiB)]
Recording Speeds: [2.4x, 3.3x-8x]