diff --git a/ch07_authorization-authentication.adoc b/ch07_authorization-authentication.adoc
index b2717d55..6d589706 100644
--- a/ch07_authorization-authentication.adoc
+++ b/ch07_authorization-authentication.adoc
@@ -134,7 +134,7 @@ image::images/mbc3_0701.png["input_and_output_scripts"]
 
 ===== The script execution stack
 
-Bitcoin's scripting language is called a stack-based language because it
+Bitcoin's ((("scripts", "stack", id="script-stack")))((("stack", id="stack")))scripting language is called a stack-based language because it
 uses a data structure called a _stack_. A stack is a very simple data
 structure that can be visualized as a stack of cards. A stack has two
 base operations: push and pop. Push adds an item on top of the stack. Pop
@@ -152,7 +152,7 @@ of +TRUE+ or +FALSE+. For example, +OP_EQUAL+ pops two items from the stack
 and pushes +TRUE+ (+TRUE+ is represented by the number 1) if they are equal
 or +FALSE+ (represented by zero) if they are not equal. Bitcoin
 transaction scripts usually contain a conditional operator, so that they
-can produce the +TRUE+ result that signifies a valid transaction.
+can produce the +TRUE+ result that signifies a valid ((("scripts", "stack", startref="script-stack")))((("stack", startref="stack")))transaction.
 
 ===== A simple script