DELHI UNIVERSITY E-LIBRARY: https://du.refread.com/#/home
DELHI UNIVERSITY LIBRARY SYSTEM (DULS): http://crl.du.ac.in/
NATIONAL DIGITAL LIBRARY OF INDIA: Virtual Repository of innumerable learning resources and MOOCs on all subjects: https://ndl.iitkgp.ac.in/
Online Teaching & Learning - DU's Virtual Learning Environment - http://www.du.ac.in/index.php?page=online-teaching-learning
Delhi University Library System (DULS) e-Resources: http://crl.du.ac.in/sub.database/SUBS.E-RESOURCE.htm
Other e-Resources of DULS: http://www.du.ac.in/index.php?page=libraries
DELHI UNIVERSITY PREVIOUS YEARS' QUESTION PAPERS:
Link 1: https://www.tutorialsduniya.com/du-previous-year-question-papers/
Link 2: https://www.kalindicollege.in/previous-year-qpapers/
Link 3: https://www.deshbandhucollege.ac.in/library-old-question-papers.php
SUGAMYA PUSTAKALAYA FOR VISUALLY IMPAIRED AND OTHER PRINT DISABLED PERSONS: https://library.daisyindia.org/NALP/welcomeLink.action
www.refseek.com - Academic Resource Search. More than a billion sources: encyclopedia, monographies, magazines.
www.worldcat.org - a search for the contents of 20 thousand worldwide libraries. Find out where lies the nearest rare book you need.
https://link.springer.com - access to more than 10 million scientific documents: books, articles, research protocols.
www.bioline.org.br is a library of scientific bioscience journals published in developing countries.
http://repec.org - volunteers from 102 countries have collected almost 4 million publications on economics and related science.
www.science.gov is an American state search engine on 2200+ scientific sites. More than 200 million articles are indexed.
www.pdfdrive.com is the largest website for free download of books in PDF format. Claiming over 225 million names.
www.base-search.net is one of the most powerful researches on academic studies texts. More than 100 million scientific documents, 70% of them are free.
E-Books in Different Subjects - 4eBooks has a huge collection of computer programming ebooks. http://4ebooks.org/
Arts & Photography - http://www.e-booksdirectory.com/listing.php?category=108
Ask Sam Ebooks has a collection of free e-books like Shakespeare, and assorted legal & governmental texts. - http://www.asksam.com/ebooks/
Audio books - http://www.audible.com/t1/PBRP0329WS022409?source_code=PBRP0310WS012709
Baen Free Library is an online library of downloadable science fiction novels - http://www.baen.com/library/
Biographies & Memoirs - http://www.e-booksdirectory.com/listing.php?category=146
Z-Library provides free downloadable ebooks in various subjects - https://1lib.in/
Book Yards is a web portal which contains books, education materials, information etc. -http://www.bookyards.com/
Brill Open E-Book Collection - http://booksandjournals.brillonline.com/content/books
Business & Investing - http://www.e-booksdirectory.com/listing.php?category=118
Computers Science & Internet - http://www.e-booksdirectory.com/listing.php?category=9
Darwin Online - http://darwin-online.org.uk/
Directory of Open access Books - http://www.doabooks.org/
eBookLobby containing collection of various subjects. - http://www.ebooklobby.com/
Engineering & Technology - http://www.e-booksdirectory.com/listing.php?category=73
Entertainment & Games- http://www.e-booksdirectory.com/listing.php?category=21
ENVIS Bulletin "Telemetry in Wildlife Science"- http://www2.wii.gov.in/envis/telemetry/index.html
Free Book Spot is an online source of free ebooks download with 4485 Titles in various subjects- http://www.freebookspot.es/
Free Computer Books consists of a huge collection of free online Computer, Programming, Mathematics, Technical Books- http://freecomputerbooks.com/
Free Tech Books lists free online computer science, engineering and programming books, textbooks and lecture notes- http://www.freetechbooks.com/
Get Free EBooks- http://www.getfreeebooks.com/
Globusz is a unique ePublishing house, specializing in free eBook downloads- http://www.globusz.com/
Gutenberg- more than 20,000 public domain books that are out of copyright and also world’s greatest fiction available.- http://www.gutenberg.org/
Health, Mind & Body- http://www.e-booksdirectory.com/listing.php?category=83
Historical Mathematics Collection- http://quod.lib.umich.edu/u/umhistmath/
History- http://www.e-booksdirectory.com/listing.php?category=110
Humanities- http://www.e-booksdirectory.com/listing.php?category=282
Know Free is a web portal where users are able to exchange freely e-books, video training and other materials for educational purposes and self-practice- http://knowfree.net/
Law- http://www.e-booksdirectory.com/listing.php?category=268
Literature & Fiction- http://www.e-booksdirectory.com/listing.php?category=74
Many Books provides more than 20,000 ebooks in various subjects- http://www.manybooks.net/
Mathematics- http://www.e-booksdirectory.com/listing.php?category=3
Medical Science- http://www.e-booksdirectory.com/listing.php?category=77
Memo Ware has a unique collection of thousands of documents (databases, literature, maps, technical references, lists, etc.)- http://www.memoware.com/
Nonfiction- http://www.e-booksdirectory.com/listing.php?category=19
Online Books for children- http://www.biguniverse.com/
Online Computer Books- http://www.onlineprogrammingbooks.com/
Best Open Access Resources: Following is the list of some best ICT initiatives (India and abroad) with their access link:
National Digital Library https://ndl.iitkgp.ac.in/
SWAYAM Online Courses https://storage.googleapis.com/uniquecourses/online.html
National Knowledge Network https://nkn.gov.in/
NPTEL https://finptel.ac.in
InfoPort https://infoport.inflibnet.ac.in/
Talks to Teacher https://www.ted.com/playlists/182/talks_from_inspiring_teachers
A-VIEW http://aview.in/
Virtual Labs https://www.vlab.co.in/
FOSSEE https://fossee.in/
Spoken Tutorial https://spoken-tutorial.org/
e-Yantra https://www.e-yantra.org/
12. Oscar++ https:////www.it.iitb.ac.in/oscar/
NCERT Text Books http://ncert.nic.in/textbook/textbook.htm
Directory of Open Access Books https://www.doabooks.org/
Directory of Open Access Journals https://doaj.org/
Open Knowledge Repository — World Bank https://openknowledge.worldbank.org/
UG/PG MOOCs http://ugcmoocs.inflibnet.ac.in/ugcmoocs/moocs_courses.php
e-PG Pathshala https://epgp.inflibnet.ac.in/
e-Content courseware in UG subjects http://cec.nic.in/cec/
SWAYAMPRABHA https://www.swayamprabha.gov.in
e-Shodh Sindhu https://ess.inflibnet.ac.in/
SNLTR https://www.nltr.org/
Oxford Open https://academic.oup.com/journals/pages/open_access
Cambridge University Press https://www.cambridge.org/core/what-we-publish/open-access
Science Direct Open Access Content https://www.sciencedirect.com/book/9781843342038/open-access
ILOSTAT https://ilostat.ilo.org/
Project Euclid https://projecteuclid.org/librarians/lib_oa
AidData https://www.aiddata.org/
Springer Open Journals https://www.springeropen.com/journals
Taylor & Francis Open Access https://www.tandfonline.com/openaccess
Open Access Thesis & Dissertations- https://oatd.org/
Open Access Directories https://sites.google.com/site/shihabillias/openaccessdirectories