Dona Massin
type: MusicGroup
description: Dona Massin (born 18 February 1917–26 May 2001) was a film choreographer best known for her work on the 1939 film version of The Wizard of Oz. Dona Massin appeared in over 100 films throughout her ca
popularity: 4
followers: 6
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x0f1d4bd1ddd15ac86efe7418b5e8558fb22b9ab36f2dd770b34cb0a44d72d49e
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 953941
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/953941
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/20212b2d-90a4-4030-95ea-20a40fbd5b95.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/20212b2d-90a4-4030-95ea-20a40fbd5b95.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/20212b2d-90a4-4030-95ea-20a40fbd5b95
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-16T11:51:19Z
additional property: OTSCanonicalRecord
  type: PropertyValue
  value: {"copyright_id":"0x0f1d4bd1ddd15ac86efe7418b5e8558fb22b9ab36f2dd770b34cb0a44d72d49e","name":"Dona Massin","registered_at":"2026-06-16T01:01:43Z","symbol":"NIM0888099","token_address":"0xd749e82afec3b9f1e2daa41f2b7259164bb4e9e1","type":"artist","uuid":"20212b2d-90a4-4030-95ea-20a40fbd5b95"}
additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 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 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
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0f1d4bd1ddd15ac86efe7418b5e8558fb22b9ab36f2dd770b34cb0a44d72d49e. Chain 2 (Bitcoin): anchored in block 953941 (2026-06-16T11:51:19Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/20212b2d-90a4-4030-95ea-20a40fbd5b95.json and https://artists.proofprofile.net/proofs/artist/20212b2d-90a4-4030-95ea-20a40fbd5b95.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-16T11:51:19Z
  text: {"copyright_id":"0x0f1d4bd1ddd15ac86efe7418b5e8558fb22b9ab36f2dd770b34cb0a44d72d49e","name":"Dona Massin","registered_at":"2026-06-16T01:01:43Z","symbol":"NIM0888099","token_address":"0xd749e82afec3b9f1e2daa41f2b7259164bb4e9e1","type":"artist","uuid":"20212b2d-90a4-4030-95ea-20a40fbd5b95"}