Edited ch04_keys.adoc with Atlas code editor

ch04_keys.adoc

@@ -825,6 +825,12 @@ the software to correctly deduce the _y_ coordinate from the _x_
 coordinate and uncompress the public key to the full coordinates of the
 point. Public key compression is illustrated in <<pubkey_compression>>.
 
+
+[[pubkey_compression]]
+.Public key compression
+image::images/mbc3_0408.png["pubkey_compression"]
+
+
 Here's the same public key generated in <<public_key_derivation>>, shown as a compressed
 public key stored in 264 bits (66 hex digits) with the prefix +03+
 indicating the _y_ coordinate is odd:
@@ -845,9 +851,7 @@ key can produce a public key expressed in two different formats
 addresses. However, the private key is identical for both Bitcoin
 addresses.
 
-[[pubkey_compression]]
+
-.Public key compression
-image::images/mbc3_0408.png["pubkey_compression"]
 
 Compressed public keys are now the default in almost all Bitcoin
 software and were required when using certain new features added