sentences:  The site is a metasearch engine, integrating data from several sources, including the U.S. Library of Congress API, the Amazon.com database of books, and ISBNdb.com.OttoBib accepts ISBNs with either 10 or 13 digits.OttoBib.com was started as a hobby project in 2006 by Jonathan Otto, a then 4th year undergraduate at the University of Wisconsin–La Crosse, USA.