http://www.wolframalpha.com
https://www.oclc.org/en/oaister.html
BioOne
http://www.bioone.org
Plos One
http://journals.plos.org/plosone/
DOAJ
https://doaj.org/
https://worldwidescience.org/
Microsoft Academic
https://academic.microsoft.com/
Refseek
http://www.refseek.com/
Digital Library of the Commons (DLC)
http://dlc.dlib.indiana.edu/dlc/
CiteSeerX
http://citeseerx.ist.psu.edu/index
Science.gov
https://www.science.gov/
Google Correlate
http://www.google.com/trends/correlate/
Life Science Search Engine
http://vadlo.com/
Jurn
http://www.jurn.org/
TechStreet (de padrões)
http://www.techstreet.com/
Archiveshub
https://archiveshub.jisc.ac.uk/index.html
Strategian Science
https://www.strategian.com/
Yandex (em russo mas não apenas de ciência)
http://www.yandex.ru/
CERN Document Server
http://cds.cern.ch/
Dialnet
https://dialnet.unirioja.es/
iSEEK Education
http://education.iseek.com/iseek/home.page
https://www.oclc.org/en/oaister.html
BioOne
http://www.bioone.org
Plos One
http://journals.plos.org/plosone/
DOAJ
https://doaj.org/
https://worldwidescience.org/
Microsoft Academic
https://academic.microsoft.com/
Refseek
http://www.refseek.com/
Digital Library of the Commons (DLC)
http://dlc.dlib.indiana.edu/dlc/
CiteSeerX
http://citeseerx.ist.psu.edu/index
Science.gov
https://www.science.gov/
Google Correlate
http://www.google.com/trends/correlate/
Life Science Search Engine
http://vadlo.com/
Jurn
http://www.jurn.org/
TechStreet (de padrões)
http://www.techstreet.com/
Archiveshub
https://archiveshub.jisc.ac.uk/index.html
Strategian Science
https://www.strategian.com/
Yandex (em russo mas não apenas de ciência)
http://www.yandex.ru/
CERN Document Server
http://cds.cern.ch/
Dialnet
https://dialnet.unirioja.es/
iSEEK Education
http://education.iseek.com/iseek/home.page