Add reference implementation

Author: alfred-hodler

bip-0351.mediawiki

@@ -248,6 +248,10 @@ No specific instruction is given as to the details of the notification transacti
 
 Another opportunity exists for an existing business to attach notification payloads to transactions sent during the normal course of operations. Large withdrawal transactions from mining pools or exchanges could include a marginal notification payload without affecting overall fees.
 
+==Reference Implementation==
+
+Reference implementation is available at https://github.com/alfred-hodler/bip-351-private-payments
+
 ==Reference==
 * [[bip-0032.mediawiki|BIP32 - Hierarchical Deterministic Wallets]]
 * [[bip-0043.mediawiki|BIP43 - Purpose Field for Deterministic Wallets]]