Nocturne No. 21 in C minor, Op. posth.

Recording by Frédéric Chopin.

Recording identifiers

ISRC
KRUM71900047
CopyrightID (CopyrightChains transaction hash)
0xb040736e871cebcc614cb9e80836e7cbcf4d3640b313a83a112f50ceb7f40e92
Copyright registration time
2026-07-04T15:13:21+00:00

OpenTimestamps proof evidence

Bitcoin-attested timestamp
2026-07-08T03:20:19Z
Bitcoin block
957118
Canonical record hash
sha256:b29033d4e588d4bf43d163b5f224b91ea71c1fb1f6b630d303123bcd3dace9ce

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.