Which book by Hirohiko Araki was published on 6/6/2006?
"Hirohiko Araki" is the author_name; on 6/6/2006 refers to publication_date = '2006-06-06'; which book refers to title
SELECT T1.title FROM book AS T1 INNER JOIN book_author AS T2 ON T1.book_id = T2.book_id INNER JOIN author AS T3 ON T3.author_id = T2.author_id WHERE T3.author_name = 'Hirohiko Araki' AND T1.publication_date = '2006-06-06'