diff --git a/ch02.asciidoc b/ch02.asciidoc
index 2fde151f..7f89cd16 100644
--- a/ch02.asciidoc
+++ b/ch02.asciidoc
@@ -53,7 +53,7 @@ image::images/mbc2_0202.png["payment-request"]
 
 [TIP]
 ====
-Try to scan this with your wallet to see the address and amount but DO NOT SEND MONEY. 
+((("QR codes", "avoid using addresses appearing in book")))Try to scan this with your wallet to see the address and amount but DO NOT SEND MONEY. 
 ====
 [[payment-request-URL]]
 .The payment request QR code encodes the following URL, defined in BIP-21: