% a comment
 @preamble{ "Blah blah" }

Another comment
 @string{title = {A great title} }

 and one more comment

   @ARTICLE{Cesar2013,
  author = {Jean César},
  title = title,
  year = {2013},
  month = "jan",
  volume = {12},
  pages = {12-23},
  journal = {Nice Journal},
  abstract = {This is an abstract. This line should be long enough to test
multilines... and with a french érudit word},
  comments = {A comment},
  keyword = {keyword1, keyword2},
}