- NKUA, Department of History and Philosophy of Science
- AUTh, School of Philosophy and Education
- Alexander von Humboldt-Stiftung
- Stanford Encyclopedia of Philosophy
- The Internet Encyclopedia of Philosophy
- PhilPapers (Online research in philosophy)
- Perseus (Ancient Texts)
- Zeno.org (Philosophical Texts in German)
- Guidelines on Writing a Philosophy Paper
- Philosophy Pages
- The Philosophical Lexicon (by Daniel Dennett)
- Die Philosophie-Seiten (in German)