https://archive.org/details/wie-stark-bestimmt-produktivitat-unseren-arbeitsalltag-sternstunde-philosophie-srf-kultur
https://archive.org/details/prof.-dr.-gerd-gantefor-weltbevolkerung-sind-wir-zu-viele-oder-sterben-wir-aus
https://archive.org/details/wolfgang-wiedergut-freie-energie-und-levitation-technologie