diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index 590f42af3b..32c79acfe2 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -2464,7 +2464,7 @@ This section is divided into Normative and Informative references.  Normative re
 ## Informative
 <a id="ref-casper-ffg"></a> _**casper-ffg**_ </br> &nbsp; _Casper the Friendly Finality Gadget_. V. Buterin and V. Griffith. URL: https://arxiv.org/abs/1710.09437
 
-<a id="ref-python-poc"></a> _**python-poc**_ </br> &nbsp; _Python proof-of-concept implementation_. Ethereum Foundation. URL: https://github.com/ethereum/beacon_chain
+<a id="ref-python-poc"></a> _**python-poc**_ </br> &nbsp; _Python proof-of-concept implementation_. Ethereum Foundation. URL: https://github.com/ethereum/trinity/tree/master/eth2
 
 # Copyright
 Copyright and related rights waived via [CC0](https://creativecommons.org/publicdomain/zero/1.0/).