diff --git a/semester4/ps/ps-jh/probability-and-statistics-cheatsheet.pdf b/semester4/ps/ps-jh/probability-and-statistics-cheatsheet.pdf
index 1e23939..116cd5a 100644
Binary files a/semester4/ps/ps-jh/probability-and-statistics-cheatsheet.pdf and b/semester4/ps/ps-jh/probability-and-statistics-cheatsheet.pdf differ
diff --git a/semester4/ps/ps-jh/probability-and-statistics-cheatsheet.tex b/semester4/ps/ps-jh/probability-and-statistics-cheatsheet.tex
index 8f3a574..7dfdb39 100644
--- a/semester4/ps/ps-jh/probability-and-statistics-cheatsheet.tex
+++ b/semester4/ps/ps-jh/probability-and-statistics-cheatsheet.tex
@@ -15,6 +15,8 @@
 \startDocument
 \noverticalspacing
 
+% TODO: Short combinatorics summary
+
 \section{Basics}
 \input{parts/00_basics/00_probability-space.tex}
 \input{parts/00_basics/01_examples-probability-spaces.tex}