A system issue is affecting the performance of Ebook Central and its search function is down. They are working quickly to fix the issue, and we'll update you as soon as we know more.
You can see also see live status information and sign up for the system to notify you of outages and maintenance here: https://status.proquest.com/
Ebook Central's search function is restored as of 9:28PM on 6/26/20.