diff --git a/app/graphql/types/record_type.rb b/app/graphql/types/record_type.rb
index 1d7a5e09..0f0b27df 100644
--- a/app/graphql/types/record_type.rb
+++ b/app/graphql/types/record_type.rb
@@ -249,7 +249,7 @@ def dois
     end
 
     def deprecated_identifiers(field)
-      @object['identifiers'].map { |id| id['value'] if id['kind'] == field }.compact
+      @object['identifiers']&.map { |id| id['value'] if id['kind'] == field }&.compact
     end
   end
 end
diff --git a/test/graphql/types/record_type_test.rb b/test/graphql/types/record_type_test.rb
index 0c5574be..f533e306 100644
--- a/test/graphql/types/record_type_test.rb
+++ b/test/graphql/types/record_type_test.rb
@@ -30,4 +30,10 @@ class RecordTypeTest < ActiveSupport::TestCase
     result = record_type.file_formats
     assert_equal %w[PDF EPUB], result, 'file_formats should return unique values'
   end
+
+  test 'deprecated identifiers return nil when identifiers key is missing' do
+    record_type = Types::RecordType.send(:new, { 'title' => 'Test Record' }, {})
+
+    assert_nil record_type.isbns
+  end
 end