diff --git a/ch12_mining.adoc b/ch12_mining.adoc
index b74f98da..02f21a5b 100644
--- a/ch12_mining.adoc
+++ b/ch12_mining.adoc
@@ -895,7 +895,7 @@ terahash per second or 1 TH/sec) would only find a solution once every
 [[target]]
 ==== Retargeting to Adjust Difficulty
 
-As we saw, the target determines the difficulty and
+As we saw, ((("bitcoins", "mining", "adjusting difficulty", id="bitcoin-mining-difficulty")))((("mining", "adjusting difficulty", id="mining-difficulty")))((("targets", "adjusting difficulty", id="target-difficulty")))((("Proof-of-Work algorithm", "adjusting difficulty", id="proof-difficulty")))((("difficulty", "adjusting", id="difficulty-adjust")))the target determines the difficulty and
 therefore affects how long it takes to find a solution to the
 Proof-of-Work algorithm. This leads to the obvious questions: Why is the
 difficulty adjustable, who adjusts it, and how?
@@ -998,7 +998,7 @@ possible with the current generation of silicon fabrication, converting
 electricity into hashing computation at the highest rate possible. The
 primary influence on the mining market is the price of one kilowatt-hour
 of electricity in bitcoin, because that determines the profitability of
-mining and therefore the incentives to enter or exit the ((("candidate blocks", "mining", startref="candidate-mine")))((("blocks", "candidate blocks", "mining", startref="block-candidate-mine")))((("mining", "candidate blocks", startref="mining-candidate")))((("bitcoins", "mining", "candidate blocks", startref="bitcoin-mining-candidate")))mining
+mining and therefore the incentives to enter or exit the ((("candidate blocks", "mining", startref="candidate-mine")))((("blocks", "candidate blocks", "mining", startref="block-candidate-mine")))((("mining", "candidate blocks", startref="mining-candidate")))((("bitcoins", "mining", "candidate blocks", startref="bitcoin-mining-candidate")))((("bitcoins", "mining", "adjusting difficulty", startref="bitcoin-mining-difficulty")))((("mining", "adjusting difficulty", startref="mining-difficulty")))((("targets", "adjusting difficulty", startref="target-difficulty")))((("Proof-of-Work algorithm", "adjusting difficulty", startref="proof-difficulty")))((("difficulty", "adjusting", startref="difficulty-adjust")))mining
 market.
 
 [[mtp]]