Crossref

R Discovery

discovery.researcher.life

Open Library

openlibrary.org

Zotero

zotero.org

ProQuest RefWorks

refworks.proquest.com

Scopus

scopus.com

Web of Science

webofscience.com

ReadCube

readcube.com

Springer

springer.com

Research Square

researchsquare.com

Petal Cite

petal.org

ProQuest

proquest.com

Citationsy

citationsy.com

CORE

core.ac.uk

F1000 research

f1000research.com

BibSonomy

bibsonomy.org

R Concept

covid19.researcher.life

Citasion

citasion.com

ROAD

road.issn.org

Hindawi

hindawi.com

DataCite Commons

commons.datacite.org

References.net

references.net

Refden

refden.com

Cambrian

cambrianml.org

ssrn.com

ssrn.com