B1
the writer of a book, article, play, etc.
Dictionary examples:
The author of 'How to Get Rich' couldn't afford a pencil. (0.0)
The author of 'How to Sleep at Work' was fired immediately. (0.0)
The author of 'How to Cook Socks' became rich overnight. (0.0)
He is the author of two books on French history. (54.0)