The Silesian String Quartet is a string quartet founded in 1978 by the graduates of the Karol Szymanowski Academy of Music in Katowice, Poland. Its current members are: Szymon Krzeszowiec (violin I)
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 0xe8d7c2669598b9abf683ed9a4e4df1abf8df7b642d98d8fbc8b1dd12d4271207. Chain 2 (Bitcoin): anchored in block 953742 (2026-06-15T04:47:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/93eb29e4-0291-47cf-bc6e-6399cc7290c8.json and https://artists.proofprofile.net/proofs/artist/93eb29e4-0291-47cf-bc6e-6399cc7290c8.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Bacewicz: Two Piano Quintets, Quartet for Four Violins & Quartet for Four Cellos