Multilanguage files, get All versions(each language) of a si

I have a site with multilanguage.

In documents and files I added files with their corresponding version in each language.

I want to get all versions of the selected document.

I did this:

public void GetDocumentLanguageVersions(IEnumerable<Guid> documentsId)
{

      var librariesManager = LibrariesManager.GetManager();
      List<Document> documents = librariesManager.GetDocuments().Where(document =>documentsId.Contains(document.Id)).ToList();  
      Document proof = documents.FirstOrDefault();
      string[] languages = proof.AvailableLanguages;
      var languageData = proof.LanguageData;  //In this object I can see the number of languages ​​available for this document but it does not show me the ids

}

Thanks in advanced.