diff --git a/main.tex b/main.tex
index 39d27883ce16c8f6d527d3d872c1319d0151e357..8a0f05a6f6094b4a96cb22faee3f590196e56a93 100644
--- a/main.tex
+++ b/main.tex
@@ -18,6 +18,7 @@
 \newcommand{\M}{\mathcal{M}}
 \newcommand{\sq}{\square}
 \newcommand{\lett}{\text{let}\,\,}
+\newcommand{\ret}{\text{ret}\,\,}
 
 \begin{document}
 \title{Call-by-value Gradual Type Theory}