A simple wordcloud, when it displays hierarchically structured information, can tell instantly something both very significant and onerous to establish otherwise. One would have to browse through hundreds of bibliographical data and to sort them, before being able to discover what the cloud above suggests simply and immediatly.
The author who published the most books in the Penguin Crime Club, the famous British pocketbooks publisher’s subseries devoted to the classics of crime fiction, is actually not Agatha Christie, nor a member of the detection club, nor any British author. Neither is it one of the prolific American masters, such as Ellery Queen, or Erle Stanley Gardner. It is actually Georges Simenon, with 48 books published under the universally recognised green cover.