diff --git a/ch04_keys.adoc b/ch04_keys.adoc
index 06ed966d..6765269a 100644
--- a/ch04_keys.adoc
+++ b/ch04_keys.adoc
@@ -508,7 +508,7 @@ For example, imagine I want to ask you a question and also give you my
 answer in a form that you can't read immediately.  Let's say the
 question is, "in what year did Satoshi Nakamoto start working on
 Bitcoin?"  I'll give you a commitment to my answer in the form of
-output from the SHA256 hash function, the function most commonly used in
+output from the((("SHA256 hash function"))) SHA256 hash function, the function most commonly used in
 Bitcoin:
 
 ----
@@ -533,7 +533,7 @@ was the exact same key that was used to create that earlier commitment.
 The SHA256 hash function is considered to be very secure and produces
 256 bits (32 bytes) of output, less than half the size of original
 Bitcoin public keys.  However, there are other slightly less secure hash
-functions that produce smaller output, such as the RIPEMD160 hash
+functions that produce smaller output, such as the ((("RIPEMD160 hash function")))RIPEMD160 hash
 function whose output is 160 bits (20 bytes).  For reasons Satoshi
 Nakamoto never stated, the original version of Bitcoin made commitments
 to public keys by first hashing the key with SHA256 and then hashing