-    $filters{numberfield}   = $type eq 'service' ? 'servicenumber' : 'articlenumber';
-    $filters{numberfield}   = $type eq 'assembly' ? 'assemblynumber' : $filters{numberfield};
+    my %numberfield_hash = ( service    => 'servicenumber',
+                             assembly   => 'assemblynumber',
+                             assortment => 'assortmentnumber',
+                             part       => 'articlenumber'
+                           );
+    $filters{numberfield}   = $numberfield_hash{$type};