A Santa Sé – https://www.vatican.va
Acta Apostolicae Sedis – https://www.vatican.va/archive/aas/index_sp.htm
Acta Sanctae Sedis – https://www.vatican.va/archive/ass/index_ge.htm
Acta Sanctorum – https://www.documentacatholicaomnia.eu/25_90_1643-1925-_Acta_Sanctorum.html
Augustinus Hipponensis – https://www.augustinus.it/
Biblia Clerus – https://www.clerus.org/bibliaclerus/index_por.html
Christian Classics Ethereal Library – https://www.ccel.org/
Corpus Corporum – https://mlat.uzh.ch/
Corpus Thomisticum – https://www.corpusthomisticum.org
Depósito Académico Digital Universidad de Navarra – https://dadun.unav.edu/
Documenta Catolica Omnia – https://www.documentacatholicaomnia.eu/
Internet Archive – https://archive.org
Internet Medieval Sourcebook – https://origin-rh.web.fordham.edu/Halsall/sbook.asp
Jewish Encyclopedia – https://jewishencyclopedia.com
KathPedia – https://www.kathpedia.de
Mansi, Sacrorum Conciliorum Nova et Amplissima Collectio – https://patristica.net/mansi
Münchener Digitalisierungszentrum – https://www.digitale-sammlungen.de/de
New Advent – https://www.newadvent.org
Patrologia Graeca – https://www.migne.com.br/
Patrologia Latina (Migne) – https://mlat.uzh.ch/browser?path=/38 – https://www.migne.com.br/#latina
Patrologia Orientalis – https://www.migne.com.br/#oriental
Perseus Digital Library – https://www.perseus.tufts.edu/hopper/collections
PONS – Dicionário online – https://pt.pons.com/tradu%C3%A7%C3%A3o
Stanford Encyclopedia of Philosophy – https://plato.stanford.edu/contents.html
The Tertullian Project – https://www.tertullian.org/
Thesaurus Linguae Graece – https://stephanus.tlg.uci.edu/
WorldCat – https://search.worldcat.org/pt