https://campustechnology.com/articles/2009/02/26/penn-libraries-and-kirtas-make-200000-public-domain-books-available-for-research-and-purchase.aspx
Penn Libraries and Kirtas Make 200000 Public Domain Books Available for Research and Purchase --...
The University of Pennsylvania Libraries has begun working with Kirtas Technologies to make 200,000 titles available to the public in a unique arrangement....
books available for research