diff --git a/include/boost/cast.hpp b/include/boost/cast.hpp
index 0dfa01f..c4ce8d3 100644
--- a/include/boost/cast.hpp
+++ b/include/boost/cast.hpp
@@ -100,6 +100,6 @@ namespace boost
 
 } // namespace boost
 
-#include <boost/numeric/conversion/cast.hpp>
+# include <boost/numeric/conversion/cast.hpp>
 
 #endif  // BOOST_CAST_HPP