gistfile1.sql

SELECT `author`.`id`, `author`.`first_name`, `author`.`last_name`
FROM `author`
INNER JOIN `author_books`
ON (`author`.`id` = `author_books`.`author_id`)
WHERE `author_books`.`book_id`
IN (SELECT U0.`id`
     FROM `book` U0
     INNER JOIN `bookstore_books` U1
     ON (U0.`id` = U1.`book_id`)
     WHERE U1.`bookstore_id` = 1 )