Les Double Six (also known as the Double Six of Paris) was a French vocal jazz group established in 1959 by Mimi Perrin. The group established an international reputation in the early 1960s. The name
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 0xee9ca836efc4b6eed83d71146ad0ac67149f8e597440612625acd44a968399df. Chain 2 (Bitcoin): anchored in block 954573 (2026-06-20T15:45:29Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b435679e-8da4-42d7-90d1-13dc1fc1c07d.json and https://artists.proofprofile.net/proofs/artist/b435679e-8da4-42d7-90d1-13dc1fc1c07d.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Jazz Stars Series: The Double Six Meet Quincy Jones (Stereo Version)
Jazz Stars Séries: Les Double Six rencontrent Quincy Jones (Mono Version)
Jazz Stars Series: Les Double Six (Stereo Version)
We're Listening To Les Double Six, Vol. 1
We're Listening To Les Double Six, Vol. 2
Les Double Six rencontrent Quincy Jones (1960)