diff --git a/ch07_authorization-authentication.adoc b/ch07_authorization-authentication.adoc
index f49b400f..79f413c1 100644
--- a/ch07_authorization-authentication.adoc
+++ b/ch07_authorization-authentication.adoc
@@ -615,7 +615,7 @@ If the redeem script hash matches, the redeem script is executed:
 ==== P2SH Addresses
 
 Another
-important part of the P2SH feature is the ability to encode a script
+important ((("addresses", "P2SH")))part of the P2SH feature is the ability to encode a script
 hash as an address, as defined in BIP13. P2SH addresses are base58check
 encodings of the 20-byte hash of a script, just like Bitcoin addresses
 are base58check encodings of the 20-byte hash of a public key. P2SH