The Directory of Open Access Books is a service of OAPEN Foundation. The DOAB allows users to search for open access books on a variety of topics. Subject areas include agriculture and food sciences, business and economics, general works, health sciences, mathematics and statistics, social sciences, and many more.
HathiTrust is a partnership of institutions, offering a collection of millions of titles digitized from libraries around the world. However not all titles are available in full text due to copyright restrictions.