https://archive.org/details/gottfried-wilhelm-leibniz-monaden-und-die-theodizee
https://archive.org/details/juergen-habermas-philosophie-und-gesellschaft
https://archive.org/details/steffen-jacobsen-schach-mit-dem-tod-1 ^
https://archive.org/details/steffen-jacobsen-schach-mit-dem-tod-2
https://archive.org/details/anton-zeilinger-wissenschaft-und-religion
https://archive.org/details/die-zapfen-handtaschen-der-anunnaki-pso
https://archive.org/details/korpersprache-entschlusselt-arte
https://archive.org/details/schmetterlinge-quelle-der-inspiration-arte
https://archive.org/details/symbology-ist-die-aufklarung-gescheitert