diff --git a/src/Paragraph.cpp b/src/Paragraph.cpp
index 67ca915d10..80a7009c81 100644
--- a/src/Paragraph.cpp
+++ b/src/Paragraph.cpp
@@ -1658,7 +1658,7 @@ docstring Paragraph::expandLabel(LayoutPtr const & layout,
 		size_t const j = fmt.find('@', i + 1);
 		if (j != docstring::npos) {
 			docstring parent(fmt, i + 1, j - i - 1);
-			docstring label = from_ascii("XXXX");
+			docstring label = from_ascii("??");
 			if (tclass.hasLayout(parent))
 				docstring label = expandLabel(tclass[parent], bparams,
 						      process_appendix);