diff -r bf2db886a543 -r 92d854be33d5 plugins/redmine_bibliography/app/models/authorship.rb
--- a/plugins/redmine_bibliography/app/models/authorship.rb
+++ b/plugins/redmine_bibliography/app/models/authorship.rb
@@ -58,7 +58,7 @@
 
   def search_author_id
     if self.author.nil?
-      authid = "xxx"
+      authid = ""
     else
       authid = author_id
     end