+ def write_dewey
+ book_ids = @store.query_books_by_ddc()
+ puts 'Non-fiction books arranged by Dewey Decimal Classification: ' + book_ids.length.to_s() + ' books.'
+
+ page = Page.new(@store)
+ page.output_dir = 'ddc'
+ page.index_file = 'index.html'
+ page.title = "Non-fiction books arranged by Dewey Decimal call number"
+ page.up = ['../output/index.html', 'Up']
+
+ page.write_html(book_ids)
+ return book_ids.length
+ end
+