diff --git a/contracts/chain-adapters/Ethereum_Adapter.sol b/contracts/chain-adapters/Ethereum_Adapter.sol
index 9a315612b..46e7afce5 100644
--- a/contracts/chain-adapters/Ethereum_Adapter.sol
+++ b/contracts/chain-adapters/Ethereum_Adapter.sol
@@ -52,7 +52,7 @@ contract Ethereum_Adapter is AdapterInterface {
         emit TokensRelayed(l1Token, l2Token, amount, to);
     }
 
-    // Note: this snippet of code is copied from Governor.sol.
+    // Note: this snippet of code is copied from Governor.sol. Source: https://github.com/UMAprotocol/protocol/blob/5b37ea818a28479c01e458389a83c3e736306b17/packages/core/contracts/oracle/implementation/Governor.sol#L190-L207
     function _executeCall(address to, bytes memory data) private {
         // Note: this snippet of code is copied from Governor.sol and modified to not include any "value" field.
         // solhint-disable-next-line no-inline-assembly