diff --git a/doc/goops/Makefile.am b/doc/goops/Makefile.am
index 1506208c4..1f7d46998 100644
--- a/doc/goops/Makefile.am
+++ b/doc/goops/Makefile.am
@@ -23,6 +23,7 @@ AUTOMAKE_OPTIONS = gnu
 
 info_TEXINFOS = goops.texi
 
-goops_TEXINFOS = goops-tutorial.texi hierarchy.eps hierarchy.png hierarchy.txt
+goops_TEXINFOS = goops-tutorial.texi \
+  hierarchy.eps hierarchy.png hierarchy.txt hierarchy.pdf
 
 TEXINFO_TEX = ../ref/texinfo.tex