Digital Library

World Digital Libraries : https://www.wdl.org/en/
National Digital Libraries : https://ndl.iitkgp.ac.in
National Science Digital Library : https://nsdl.oercommons.org
TamilNadu Digital Library : http://www.tndigitallibrary.ac.in
eGyanKosh (IGNOU) : http://www.egyankosh.ac.in
Directory of Open Access Repositories : http://v2.sherpa.ac.uk/opendoar
Open Access Library : http://www.oalib.com
InternetAchieve : https://archive.org
The Universal Digital Library Million Book Collection : https://www.ulib.org
Virtual Library : http://vlib.org
Hathi Trust Digital Library : https://www.hathitrust.org
WorldWideScience.org : https://worldwidescience.org