diff --git a/ch04_keys.adoc b/ch04_keys.adoc
index be604b31..88145b8a 100644
--- a/ch04_keys.adoc
+++ b/ch04_keys.adoc
@@ -178,7 +178,7 @@ image::images/mbc3_0402.png["ecc-curve"]
 Bitcoin uses a specific elliptic curve and set of mathematical
 constants, as defined in a standard called +secp256k1+, established by
 the National Institute of Standards and Technology (NIST). The
-+secp256k1+ curve is defined by the following function, which produces
++secp256k1+ curve is defined by the following equation, which produces
 an elliptic curve:
 
 [latexmath]
@@ -777,7 +777,7 @@ results in smaller transactions, allowing more payments to be made in the same
 block.
 
 As we saw in the section <<public_key_derivation>>, a public key is a point [.keep-together]#(x, y)# on an
-elliptic curve. Because the curve expresses a mathematical function, a
+elliptic curve. Because the curve expresses a mathematical mapping, a
 point on the curve represents a solution to the equation and, therefore,
 if we know the _x_ coordinate, we can calculate the _y_ coordinate by
 solving the equation [.keep-together]#y^2^ mod p = (x^3^ + 7) mod p.# That allows us to
diff --git a/meta/github_contrib.adoc b/meta/github_contrib.adoc
index 6bb33810..edaad114 100644
--- a/meta/github_contrib.adoc
+++ b/meta/github_contrib.adoc
@@ -189,6 +189,7 @@
 <li>yurigeorgiev4</li>
 <li>Zheng Jia (zhengjia)</li>
 <li>Zhou Liang (zhouguoguo)</li>
+<li>Suyang Liu (LiuYusuf)</li>
 </ul>
 ++++