diff --git a/.gitmodules b/.gitmodules
index eda9f20..48b96ec 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,6 @@
 [submodule "sose2020/ana/lectures"]
 	path = sose2020/ana/lectures
 	url = https://git.flavigny.de/christian/ana-lecture
+[submodule "sose2020/num/hdnum"]
+	path = sose2020/num/hdnum
+	url = https://parcomp-git.iwr.uni-heidelberg.de/Teaching/hdnum
diff --git a/sose2020/num/hdnum b/sose2020/num/hdnum
new file mode 160000
index 0000000..206ffca
--- /dev/null
+++ b/sose2020/num/hdnum
@@ -0,0 +1 @@
+Subproject commit 206ffcacaf32199b4d284d720db004bdde8a03c0