Xuân Quỳnh (6 October 1942 – 29 August 1988) was a famous modern female Vietnamese poet. She, her husband Lưu Quang Vũ, and their 13-year-old son Lưu Quỳnh Thơ died in a car accident in Hải Dương city
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x25fcae7a7c9d9a6cfa5d755ff8b277afe2f80f616e7462517b1b10f548d378ee. Chain 2 (Bitcoin): anchored in block 954705 (2026-06-21T13:42:37Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/f2bd95dd-880d-4b94-b631-258ddc7e8901.json and https://artists.proofprofile.net/proofs/artist/f2bd95dd-880d-4b94-b631-258ddc7e8901.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).