diff --git a/Doc/tools/whichlibs b/Doc/tools/whichlibs
index 56287cbee36..10d44ee717a 100755
--- a/Doc/tools/whichlibs
+++ b/Doc/tools/whichlibs
@@ -1,2 +1,2 @@
 #!/bin/sh
-sed -n 's/^\\input{\(lib[a-zA-Z0-9_]*\)}.*/\1.tex/p' lib.tex
+sed -n 's%^\\input{\(lib[a-zA-Z0-9_]*\)}.*%../lib/\1.tex%p' ../lib/lib.tex