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type: MusicGroup
genre: chamber music
popularity: 2
followers: 1
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additional property: OTSVerifyInstructions
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subject of: OpenTimestamps Proof of Existence
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  date published: 2026-06-19T03:22:39Z
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track: Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: I. Allegro
track: Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: III. Rondeau: Allegro
track: Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: I. Allegro moderato
track: Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: II. Andante
track: Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: III. Allegro

Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: I. Allegro
type: MusicRecording
duration: PT6M33S
duration ms: 393900
explicit: false
by artist: Endres Quartet
by artist: Alfred Sous
by artist: Adolph Schmidt
by artist: Heinz Endres
by artist: Fritz Ruf
in album: Mozart, Schubert, Ravel and Janácek: Chamber Music Selections
  type: MusicAlbum
  date published: 2010-12-28
isrc code: USZDG0602417
additional property: CopyrightID
additional property: CopyrightStatus
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additional property: CopyrightRegisteredAt
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additional property: OTSVerificationAPI
  type: PropertyValue
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additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-07-08T03:20:19+00:00
additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 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
additional property: ProofProfileEvidenceStatus
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additional property: TokenDeploymentConfirmed
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additional property: ContentHash
additional property: BitcoinBlock
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additional property: BitcoinTime
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subject of: OpenTimestamps Proof of Existence
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  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5d79f17b7c72adaf191c55c34efe1ccb65174ea6365ef0e5a4100ffeeac53c13. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/USZDG0602417.
  date published: 2026-07-08T03:53:27Z
audio: Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: I. Allegro
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  additional property: Tempo (BPM)
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  additional property: Musical Key
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Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: III. Rondeau: Allegro
type: MusicRecording
duration: PT4M41S
duration ms: 281077
explicit: false
by artist: Endres Quartet
by artist: Fritz Ruf
by artist: Alfred Sous
by artist: Adolph Schmidt
by artist: Heinz Endres
in album: Mozart, Schubert, Ravel and Janácek: Chamber Music Selections
  type: MusicAlbum
  date published: 2010-12-28
isrc code: USZDG0602419
additional property: CopyrightID
additional property: CopyrightStatus
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additional property: OTSVerificationAPI
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additional property: OTSTimestamp
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additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 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
additional property: ProofProfileEvidenceStatus
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additional property: TokenDeploymentConfirmed
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additional property: ContentHash
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additional property: BitcoinTime
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subject of: OpenTimestamps Proof of Existence
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  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcb673ea793ccee40b025247f6a52d9285b804bd45f8f6a30a047f4b612dc3d05. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/USZDG0602419.
  date published: 2026-07-08T03:20:19Z
audio: Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: III. Rondeau: Allegro
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  additional property: Valence (Positivity)
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  additional property: Key Name
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  additional property: Mode Name
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Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: I. Allegro moderato
type: MusicRecording
duration: PT6M24S
duration ms: 384104
explicit: false
by artist: Endres Quartet
by artist: Sebastian Huber
by artist: Adolph Schmidt
by artist: Joseph Rottenfusser
by artist: Fritz Ruf
by artist: Heinz Endres
in album: Mozart, Schubert, Ravel and Janácek: Chamber Music Selections
  type: MusicAlbum
  date published: 2010-12-28
isrc code: USZDG0602420
additional property: CopyrightID
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additional property: OTSVerificationAPI
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additional property: OTSTimestamp
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additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 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
additional property: ProofProfileEvidenceStatus
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additional property: TokenDeploymentConfirmed
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additional property: ContentHash
additional property: BitcoinBlock
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additional property: BitcoinTime
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subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
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  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x873e1b901f8050c124edc2fcd0ef2386ed1ecf165d9da5277291f6715e4c3162. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/USZDG0602420.
  date published: 2026-07-08T08:56:20Z
audio: Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: I. Allegro moderato
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  additional property: Speechiness
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  additional property: Valence (Positivity)
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  additional property: Key Name
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  additional property: Mode Name
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Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: II. Andante
type: MusicRecording
duration: PT7M0S
duration ms: 420466
explicit: false
by artist: Endres Quartet
by artist: Joseph Rottenfusser
by artist: Heinz Endres
by artist: Sebastian Huber
by artist: Adolph Schmidt
by artist: Fritz Ruf
in album: Mozart, Schubert, Ravel and Janácek: Chamber Music Selections
  type: MusicAlbum
  date published: 2010-12-28
subject of: OpenTimestamps Proof of Existence
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  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdb4ac8efae530eda1eaae9eeee766b9249ec5a7ca31fe880882e6b9ce29349ba. Chain 2 (Bitcoin): anchored in block 960387 (2026-07-31T10:06:30Z), 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/USZDG0602421.
  date published: 2026-07-31T10:06:30Z
audio: Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: II. Andante
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  additional property: Danceability
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  additional property: Energy
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  additional property: Speechiness
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additional property: CopyrightID
additional property: ProofProfileEvidenceStatus
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additional property: OTSVerificationAPI
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additional property: OTSHash
additional property: OTSBitcoinBlock
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additional property: OTSBitcoinBlockVerifyURL
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additional property: OTSTimestamp
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additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 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

Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: III. Allegro
type: MusicRecording
duration: PT3M55S
duration ms: 235183
explicit: false
by artist: Endres Quartet
by artist: Fritz Ruf
by artist: Sebastian Huber
by artist: Heinz Endres
by artist: Adolph Schmidt
by artist: Joseph Rottenfusser
in album: Mozart, Schubert, Ravel and Janácek: Chamber Music Selections
  type: MusicAlbum
  date published: 2010-12-28
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d13c1bf03a461cbd7d988f85a505e64364e9433eebc39ed5df1504739760e96. Chain 2 (Bitcoin): anchored in block 960240 (2026-07-30T09:57:33Z), 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/USZDG0602422.
  date published: 2026-07-30T09:57:33Z
audio: Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: III. Allegro
  type: AudioObject
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  additional property: Time Signature
    type: PropertyValue
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  additional property: Danceability
    type: PropertyValue
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  additional property: Energy
    type: PropertyValue
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  additional property: Speechiness
    type: PropertyValue
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  additional property: Acousticness
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  additional property: Instrumentalness
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  additional property: Valence (Positivity)
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additional property: CopyrightID
additional property: ProofProfileEvidenceStatus
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additional property: TokenDeploymentConfirmed
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additional property: ContentHash
additional property: BitcoinBlock
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additional property: BitcoinTime
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additional property: OTSVerificationAPI
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additional property: OTSHash
additional property: OTSBitcoinBlock
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additional property: OTSBitcoinBlockVerifyURL
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additional property: OTSTimestamp
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additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 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