General Resources
Stanford Encyclopedia of Philosophy
Internet Encyclopedia of Philosophy
Zedler, Universallexikon 
Corpus Iuris Civilis
General Collections
Internet Archive
Proquest dissertations
Hathi Trust Digital Library
The Logic Museum
Münchner Digitalisierungszentrum
Gallica, Bibliothèque nationale
de France 
bibliothèque numérique de Lyon
Language
Grimm's Wörterbuch
ΛOΓEION Ancient Greek / Latin Dictionary
Perseus Dictionaries
Arabic (aratools)
Arabic (Lane) 
Sanscrit
Islamic
Islamic Philosophy Online
Post-classical Islamic Philosophy Database
ZDMG
Al-Ghazali
Arabic books in pdf
Persian books in pdf 
Western Medieval
CCEL;
CSEL;
MPL (scans)
Online Medieval Sources Bibliography
Augustine, Opera Omnia 
Church Fathers (newadvent.org)
Franciscan Archive
Albertus Magnus
Aquinas: Corpus
Thomisticum
Duns Scotus Online
Suárez
Marx
Marx Engels Werke (MEW), pdf
Marx Engels Collected Works (MECW)
Marxists Internet Archive
Marxforschung
Georg Lukacs Archive 
Books
Indigo (Canada)
Better World Books
Wordery (Canada)
Alibris
SuperBookDeals
ThriftBooks
Buchfreund.de
On Avoiding Amazon
Alternatives to Amazon
Medimops (Germany)
Local Bookstores (Germany)
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