right|150px|thumb|Grave of Marie Dubas and Sylvie Galtier in Père Lachaise Cemetery Marie Dubas (3 September 1894 – 21 February 1972) was a French Jewish music-hall singer, diseuseA French Song Compa
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 0x66770210902d2b4750a6cd30ccded93ac2833b661c3b5c49ad5d8fcbdfde323f. Chain 2 (Bitcoin): anchored in block 954533 (2026-06-20T08:57:02Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/a7cf45ce-d1e2-4485-88a9-56db08633324.json and https://artists.proofprofile.net/proofs/artist/a7cf45ce-d1e2-4485-88a9-56db08633324.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp 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 0x3d98c00af0f6177002df8fab3366a8777d9fb4bd73b7b5afdb3e5d7788cfe334. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FR6V81096276.
La Chanson Française : Marie Dubas (1933 - 1945), Vol. 2
La Chanson Française : Marie Dubas (1927 - 1932), Vol. 1
Du Caf' Conc au Music-Hall (1900-1950) en 50 volumes - Vol. 17/50
Marie Dubas : La chanson du roulier (Histoire Française)
Meilleure collection française: le meilleur de Marie Dubas