diff --git a/morphology_diss.sty b/morphology_diss.sty
index 3477b5a..cdfcdd0 100644
--- a/morphology_diss.sty
+++ b/morphology_diss.sty
@@ -40,6 +40,7 @@
 \usepackage{sfmath}
 \usepackage{amssymb}
 \usepackage{amsmath}
+\usepackage{mathtools}
 \usepackage{varwidth}
 \usepackage{fontspec}
 \usepackage{graphicx}