diff --git a/catalogue/detail.pl b/catalogue/detail.pl
index 2bf81c2f78..59a6b4d6cb 100755
--- a/catalogue/detail.pl
+++ b/catalogue/detail.pl
@@ -430,7 +430,7 @@ if (C4::Context->preference("virtualshelves") ) {
 if (C4::Context->preference("FRBRizeEditions")==1) {
     eval {
         $template->param(
-            XISBNS => get_xisbns($isbn)
+            XISBNS => scalar get_xisbns($isbn)
         );
     };
     if ($@) { warn "XISBN Failed $@"; }
diff --git a/opac/opac-detail.pl b/opac/opac-detail.pl
index a7e643c4e1..5008c815af 100755
--- a/opac/opac-detail.pl
+++ b/opac/opac-detail.pl
@@ -880,7 +880,7 @@ if (C4::Context->preference("virtualshelves") ) {
 if (C4::Context->preference("OPACFRBRizeEditions")==1) {
     eval {
         $template->param(
-            XISBNS => get_xisbns($isbn)
+            XISBNS => scalar get_xisbns($isbn)
         );
     };
     if ($@) { warn "XISBN Failed $@"; }