Why can I find some duplications for the same record? 

The reasons for duplications are:  

  • If a record has more than one version (e.g., different versions of the same dataset), or 
  • If the publisher/authors/owners of the data decided to upload the data of an article with a third-party repository in which these data will get a different DOI than the original article 
  • Different DOIs were created for the same record. 

The Open Polar considers any records with a different DOI as a new record.