diff --git a/explicit-templates/Hund.cpp b/explicit-templates/Hund.cpp
index b7cc17d72ca653079ade50d8628abeed8dc65033..d6b23e51595a7876e242c30d045fab7bb959de66 100644
--- a/explicit-templates/Hund.cpp
+++ b/explicit-templates/Hund.cpp
@@ -6,12 +6,7 @@ void Hund<FOO>::bar(){
    bellen<FOO>();
 }
 
-template< class FOO>
-void bellen(){
-   std::cout << "wuff" << std::endl;
-}
-
 template class Hund<double>;
-//template void bellen<double>();
+template void bellen<double>();
 
 
diff --git a/explicit-templates/Hund.hpp b/explicit-templates/Hund.hpp
index fc6f0169e40f31e4f6256e7f0e2f18c45269b507..76ffe87dbfa2e962188bb3d4e4f266c4a80d5b3c 100644
--- a/explicit-templates/Hund.hpp
+++ b/explicit-templates/Hund.hpp
@@ -1,4 +1,5 @@
 #pragma once
+#include <iostream>
 
 template< class FOO>
 class Hund {
@@ -6,7 +7,9 @@ class Hund {
   void bar();
 };
 
-template <class FOO>
-void bellen();
+template< class FOO>
+void bellen(){
+   std::cout << "wuff" << std::endl;
+}
 
-//extern template void bellen<double>();
\ No newline at end of file
+extern template void bellen<double>();
\ No newline at end of file