diff --git a/Doc/tools/sgmlconv/fixgenents.sh b/Doc/tools/sgmlconv/fixgenents.sh
index 0503d7b..fc825c8 100755
--- a/Doc/tools/sgmlconv/fixgenents.sh
+++ b/Doc/tools/sgmlconv/fixgenents.sh
@@ -29,5 +29,17 @@
 s|<geq/>|\&ge;|g
 s|<ldots/>|\&hellip|g
 s|<leq/>|\&le;|g
+s|<ABC>|\&ABC;|g
+s|<ASCII>|\&ASCII;|g
+s|<C>|\&C;|g
+s|<Cpp>|\&Cpp;|g
+s|<EOF>|\&EOF;|g
+s|<NULL>|\&NULL;|g
+s|<POSIX>|\&POSIX;|g
+s|<UNIX>|\&UNIX;|g
+s|<e>|\&bsol;|g
+s|<geq>|\&ge;|g
+s|<ldots>|\&hellip|g
+s|<leq>|\&le;|g
 s|---|\&mdash;|g
 ' || exit $?