Wikibooks

Wikipedia

wikipedia.org

Open Library

openlibrary.org

Wiktionary

wiktionary.org

Book Creator

bookcreator.com

Wikisource

wikisource.org

OpenStax

openstax.org

Wikidata

wikidata.org

Wikiversity

wikiversity.org

Booknet

booknet.com

zyBooks

zybooks.com

Wikivoyage

wikivoyage.org

Wikitravel

wikitravel.org

Wikispecies

wikimedia.org

Wikidot

wikidot.com

Libretexts

libretexts.org

百度百科

baike.baidu.com

Python Wiki

wiki.python.org

OrthodoxWiki

orthodoxwiki.org

百度文库

wenku.baidu.com

Bookboon

bookboon.com

Literature.com

literature.com

Pressbooks

pressbooks.com

Bookwiz

bookwiz.io

Bibmath.net

bibmath.net