René Descartes - Cogito Ergo Sum - Die Geburt der Moderne. -

https://archive.org/details/rene-descartes-cogito-ergo-sum-die-geburt-der-moderne-philosophie-der-aufklarung 

https://archive.org/details/rene-descartes-ich-denke-also-bin-ich-1-grundschriften-der-europaischen-kultur

https://archive.org/details/rene-descartes-ich-denke-also-bin-ich-2-grundschriften-der-europaischen-kultur