En sourdine - for alto and piano

Recording by Pablo Casals.

Recording identifiers

ISRC
FR7JM1955150
CopyrightID (CopyrightChains transaction hash)
0x1364891d60c97373a0f0e47d2e285515591a58aee23ac3f47f7cb6ee69e2713f
Copyright registration time
2026-07-07T13:08:26+00:00

OpenTimestamps proof evidence

Bitcoin-attested timestamp
2026-07-08T03:20:19Z
Bitcoin block
957118
Canonical record hash
sha256:49d9513da41da3c45aa513ad557691c16b6e831c0b0bc4ace8acb996f1b30ae2

What this proof establishes

This recording belongs to ProofProfile's historical evidence base derived from the pre-2022 AcousticBrainz and MusicBrainz corpus. ISRC is the stable recording-level bridge from that source corpus to the authoritative cc-db-prod track record.

CopyrightChains and Bitcoin OpenTimestamps make the exact committed record independently verifiable today. The cryptographic proof does not by itself establish authorship or ownership of the underlying recording.

Read the complete pre-generative-AI provenance and verification method.