public function get($userId)
 {
     $query = Book::query();
     // TODO Include filtering the results by a list of books the user is not interested in from that author
     $books = $query->select('books.*')->joinUsersBooks($userId)->notYetPublished()->upcomingPublicationsFirst()->groupBy('user_authors.id')->get();
     $books->load('authors.author');
     return $books;
 }