diff --git a/example/demo_pimpl_A.hpp b/example/demo_pimpl_A.hpp
new file mode 100644
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--- /dev/null
+++ b/example/demo_pimpl_A.hpp
@@ -0,0 +1,24 @@
+#ifndef BOOST_SERIALIZATION_EXAMPLE_DEMO_PIMPL_A_HPP
+#define BOOST_SERIALIZATION_EXAMPLE_DEMO_PIMPL_A_HPP
+
+/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
+// demo_pimpl_A.hpp
+
+// (C) Copyright 2002 Robert Ramey - http://www.rrsd.com . 
+// Use, modification and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+// class whose declaration is hidden by a pointer
+struct B;
+
+struct A {
+    // class a contains a pointer to a "hidden" declaration
+    B *pimpl;
+    template<class Archive>
+    void serialize(Archive & ar, const unsigned int file_version);
+    A();
+    ~A();
+};
+
+#endif // BOOST_SERIALIZATION_EXAMPLE_DEMO_PIMPL_A_HPP