diff --git a/symbols.tex b/symbols.tex
index 99193ca..831a40b 100644
--- a/symbols.tex
+++ b/symbols.tex
@@ -7,8 +7,8 @@
   $\ppt$     & Probabilistic Polynomial Time            \\
   $\epsilon$ & empty word                               \\
   [1ex] \multicolumn{2}{l}{\scbf{Protocols}}            \\
-  PKE        & Public Key Encryption                    \\
-  ZK         & Zero-Knowledge                           \\
+  $\PKE$     & Public Key Encryption                    \\
+  $\ZK$      & Zero-Knowledge                           \\
   $\NIZK$    & Non-Interactive Zero-Knowledge           \\
   [1ex] \multicolumn{2}{l}{\scbf{Security Models}}      \\
   $\ROM$     & Random-Oracle Model                      \\