diff --git a/tests/misc/usage_vs_refs.sh b/tests/misc/usage_vs_refs.sh
index 48965b931..0e0d111fd 100755
--- a/tests/misc/usage_vs_refs.sh
+++ b/tests/misc/usage_vs_refs.sh
@@ -54,9 +54,9 @@ for prg in $built_programs; do
   for opt in $(getopts $prg); do
     got_option=true
     if ! grep -E "opt(Itemx?|Anchor){$dprg,$opt[,}]" \
-          $abs_top_srcdir/doc/coreutils.texi >/dev/null; then
+          "$abs_top_srcdir/doc/coreutils.texi" >/dev/null; then
       if ! grep "optItemx\\?{\\\\cmd\\\\,$opt," \
-            $abs_top_srcdir/doc/coreutils.texi >/dev/null; then
+            "$abs_top_srcdir/doc/coreutils.texi" >/dev/null; then
         printf -- '%s %s reference missing in texi\n' $dprg $opt >&2
         fail=1
       elif test "$DEBUG"; then