E-Books & Digital Library

OpenStax College (Rice University, USA - Text books for Undergraduates)

Open Text Book (Gateway to access text books of several prestigious Universities of USA)

DOAB

Hathi Trust (Collection of millions of titles digitized from libraries of academic & research institutions around the world )

World Digital Library

OAPEN (Freely accessible academic books, mainly in the area of Humanities and Social Sciences from Europe)

Digital Book Index (Search Millions of books through Single window)

National Digital Library

INTECH (Engineering and Physics)