lib/bolognese/writers/ris_writer.rb in bolognese-0.9.19 vs lib/bolognese/writers/ris_writer.rb in bolognese-0.9.20

@@ -1,8 +1,10 @@
 module Bolognese
   module Writers
     module RisWriter
       def ris
+        return nil unless valid?
+        
         {
           "TY" => ris_type,
           "T1" => title,
           "T2" => container_title,
           "AU" => to_ris(author),