diff --git a/protocols/BTP.md b/protocols/BTP.md
index 75565f2f80b125bec7516f853407f0fbfc1ec810..c7062884bc9435b8e8a670125b44d3fb547bdabe 100644
--- a/protocols/BTP.md
+++ b/protocols/BTP.md
@@ -140,7 +140,7 @@ BTP uses three cryptographic primitives:
 
 ### 2.1 Key Derivation Function
 
-BTP uses a **key derivation function** to derive encryption and authentication keys from the shared secret S. Forward secrecy relies on a one-way nature of the key derivation function.
+BTP uses a **key derivation function** to derive encryption and authentication keys from the shared secret S. Forward secrecy relies on the one-way nature of the key derivation function.
 
 The key derivation function is based on PRF(k, m):