diff --git a/ch12_mining.adoc b/ch12_mining.adoc
index d6cdc8d1..e6163686 100644
--- a/ch12_mining.adoc
+++ b/ch12_mining.adoc
@@ -308,7 +308,7 @@ _mempool_.
 
 === Mining Nodes
 
-Some of the nodes on the Bitcoin network are specialized nodes
+Some of the((("bitcoins", "mining", "miners, purpose of", id="bitcoin-mining-miner-purpose")))((("mining", "miner nodes", "purpose of", id="mining-nodes-purpose")))((("nodes", "miner nodes", "purpose of", id="nodes-miner-purpose"))) nodes on the Bitcoin network are specialized nodes
 called _miners_. Jing is a
 Bitcoin miner; he
 earns bitcoin by running a "mining rig," which is a specialized
@@ -351,7 +351,7 @@ finding a solution according to the proof-of-work algorithm.
 
 When Jing's node aggregates all the transactions from the memory pool,
 the new candidate block has several thousand transactions that each pay
-transaction fees he'll attempt to claim.
+transaction fees he'll attempt to((("bitcoins", "mining", "miners, purpose of", startref="bitcoin-mining-miner-purpose")))((("mining", "miner nodes", "purpose of", startref="mining-nodes-purpose")))((("nodes", "miner nodes", "purpose of", startref="nodes-miner-purpose"))) claim.
 
 ==== The Coinbase Transaction