diff --git a/C4/Biblio.pm b/C4/Biblio.pm
index ee0578bb79..991d32716b 100644
--- a/C4/Biblio.pm
+++ b/C4/Biblio.pm
@@ -101,6 +101,7 @@ use C4::Items qw( GetMarcItem );
 
 use Koha::Logger;
 use Koha::Caches;
+use Koha::ClassSources;
 use Koha::Authority::Types;
 use Koha::Acquisition::Currencies;
 use Koha::BackgroundJob::BatchUpdateBiblioHoldsQueue;