Offer expires on 5/9/2019 at 11:59 PM. It is non-transferable, valid in the United States only, and limited to one (1) download code for (1) e-book to the first 100 qualified responders. Multiple entries will be deleted. Please note: download codes will be sent to institutional email addresses only. Any non-institutional email address entries will be void and deleted. Please check to ensure accuracy.