Berikut daftar situs yang dapat anda kunjungi untuk menambah referensi studi Anda :
www.slideshare.net
lipi.go.id
ejournal.lipi.go.id
e-resources.perpusnas.go.id
sciencedirect.com
ijern.com
doaj.org
researchgatae.net
oapen.org
onlinelibrary.wiley.com
garuda.ristekdikti.go.id
eurekapendidikan.com
gutenberg.org
literature.com
academia.edu
academic.microsoft.com
renderforest.com
skripsi.co.id
biblehub.com
www.cambridge.org/core/what-we-publish/textbooks
www.freebiblecommentary.org
manybooks.net
openlibrary.org
www.getfreeebooks.com
www.bookyards.com
centslessbooks.com
www.ftesea.org
www.pdfdrive.net
www.globethics.net/fr/web/gtl
scholar.google.com
onesearch.id
rama.ristekdikti.go.id
sinta2.ristekdikti.go.id
muse.jhu.edu