diff --git a/include/qpdf/QPDF.hh b/include/qpdf/QPDF.hh
index c8dfcc8..286d305 100644
--- a/include/qpdf/QPDF.hh
+++ b/include/qpdf/QPDF.hh
@@ -33,6 +33,7 @@
 #include <vector>
 
 #include <qpdf/QPDFExc.hh>
+#include <qpdf/QPDFObjectHandle.hh>
 #include <qpdf/QPDFObjGen.hh>
 #include <qpdf/QPDFXRefEntry.hh>
 #include <qpdf/QPDFObjectHandle.hh>