bib <- as.BibEntry(list(c(bibtype = "Article", key = "mclean2014a", title = "My New Article", 
  author = "Mathew W. McLean", 
  journaltitle = "The Journal", date = "2014-01"), c(bibtype = "Book", key = "mclean2014b", 
  title = "My New Book", editor = "Mathew W. McLean", ISBN = "247123837", date = "2014-02")))       
fields(bib)
levels(bib)
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