diff --git a/Framework/Utilities/SaveBoostHistogram.hpp b/Framework/Utilities/SaveBoostHistogram.hpp
index 1fad5092980c92a7192bf82462001ff6dbeff6b1..d12fef8cac04dd8d8d26e2f8c5cf5f41b7cfca6c 100644
--- a/Framework/Utilities/SaveBoostHistogram.hpp
+++ b/Framework/Utilities/SaveBoostHistogram.hpp
@@ -1,3 +1,11 @@
+/*
+ * (c) Copyright 2020 CORSIKA Project, corsika-project@lists.kit.edu
+ *
+ * This software is distributed under the terms of the GNU General Public
+ * Licence version 3 (GPL Version 3). See file LICENSE for a full version of
+ * the license.
+ */
+
 #include <corsika/third_party/cnpy/cnpy.hpp>
 
 #include <boost/histogram.hpp>
@@ -8,6 +16,8 @@
 #include <utility>
 #include <vector>
 
+#pragma once
+
 namespace corsika::utl {
   /**
    * This functions saves a boost::histogram into a numpy file. Only rather basic axis