···163163164164## 9. Reference Implementation
165165166166-Deployed on Sepolia testnet: [`0x40CEB9a624E79e5bA117775D176F0059E70C92FB`](https://sepolia.etherscan.io/address/0x40CEB9a624E79e5bA117775D176F0059E70C92FB)
166166+Deployed on Sepolia testnet: [`0xB1019511Bec0F7a12B7124B28812B4428C038079`](https://sepolia.etherscan.io/address/0xB1019511Bec0F7a12B7124B28812B4428C038079)
167167168168**Contract functions (`CowRegistry.sol`):**
169169- `calculateCowHash(controller, wrappedDID)` — derive the registry key for a did:cow ID