diff --git a/src/session--composition-and-inheritance/preamble.tex b/src/session--composition-and-inheritance/preamble.tex
index f03eefd..aac2ce7 100644
--- a/src/session--composition-and-inheritance/preamble.tex
+++ b/src/session--composition-and-inheritance/preamble.tex
@@ -56,7 +56,7 @@
 \input{git}
 
 \title{Composition and inheritance}
-\subtitle{Object-oriented programming leveled up}
+\subtitle{Object-oriented programming levelled up}
 \date[2021]{\texttt{November 2021}}
 \author[Pol]{\texttt{Pol Dellaiera} - \texttt{DIGIT B4} - \texttt{DIGIT PHP SUPPORT}}
 \logo{