Why search here? You need digitized access to books and journals otherwise not available electronically.
What's included? Full-text access and downloading is available for materials published before 1923, including: US federal government documents; works still protected by copyright, but made available to HathiTrust with the permission of the copyright holder.
Why search here? You want to read graduate student dissertations and theses on a topic - often giving you extensive bibliographies, and occasionally cutting edge research on new topics.
What's included? Index of doctoral dissertations and some master's theses from most North American and many European colleges and universities. Starts in 1743. Full text is available for over 1 million, mostly since 1996.