Carlos Roldán
type: MusicGroup
genre: tango
description: Carlos Roldán (31 December 1913 – 16 June 1973), whose real name was Carlos Belarmino Porcal, was a Uruguayan tango singer with a well-known career in his country and in Argentina. Professional care
popularity: 4
followers: 14
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x51fcb3c6fd2ea3332c6d175b0da231fc7d62f56ffb872dcce387bee18c87b249
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 954549
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/954549
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/a9471f8d-0666-4f6a-9a55-ed71ccc9f255.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/a9471f8d-0666-4f6a-9a55-ed71ccc9f255.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/a9471f8d-0666-4f6a-9a55-ed71ccc9f255
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-20T10:56:20Z
additional property: OTSCanonicalRecord
  type: PropertyValue
  value: {"copyright_id":"0x51fcb3c6fd2ea3332c6d175b0da231fc7d62f56ffb872dcce387bee18c87b249","name":"Carlos Roldán","registered_at":"2026-06-20T08:56:20Z","symbol":"NIM1571505","token_address":"0xdb7100b72275a4c37c55676588f2fbfaa0b94327","type":"artist","uuid":"a9471f8d-0666-4f6a-9a55-ed71ccc9f255"}
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
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x51fcb3c6fd2ea3332c6d175b0da231fc7d62f56ffb872dcce387bee18c87b249. Chain 2 (Bitcoin): anchored in block 954549 (2026-06-20T10:56:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/a9471f8d-0666-4f6a-9a55-ed71ccc9f255.json and https://artists.proofprofile.net/proofs/artist/a9471f8d-0666-4f6a-9a55-ed71ccc9f255.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-20T10:56:20Z
  text: {"copyright_id":"0x51fcb3c6fd2ea3332c6d175b0da231fc7d62f56ffb872dcce387bee18c87b249","name":"Carlos Roldán","registered_at":"2026-06-20T08:56:20Z","symbol":"NIM1571505","token_address":"0xdb7100b72275a4c37c55676588f2fbfaa0b94327","type":"artist","uuid":"a9471f8d-0666-4f6a-9a55-ed71ccc9f255"}