Nina Cassian (pen name of Renée Annie Cassian-Mătăsaru; 27 November 1924, in Galați – 14 April 2014, in New York City) was a Romanian poet, children's book writer, translator, journalist, accomplished
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 Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbd7e4273c7033d401490cb86a86651df45b649cf1237a7098f370cf3cbb8fb9f. Chain 2 (Bitcoin): anchored in block 954549 (2026-06-20T10:56:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/aa21a1fe-3d3b-41fa-bb54-42915aa02384.json and https://artists.proofprofile.net/proofs/artist/aa21a1fe-3d3b-41fa-bb54-42915aa02384.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).