https://arduinohistory.github.io/
https://all3dp.com/history-of-the-reprap-project/
https://www.reprap.org/wiki/Ramps
https://en.wikipedia.org/wiki/Marlin_(firmware)
https://www.klipper3d.org/
https://en.wikipedia.org/wiki/OctoPrint
https://3d-drucker-test.eu/3d-drucker-arten-und-eigenschaften/
https://ultimaker.com/software/ultimaker-cura
https://www.sculpteo.com/en/3d-learning-hub/create-3d-file/fix-non-manifold-geometry/
https://blender.stackexchange.com/questions/7910/what-is-non-manifold-geometry
https://airwolf3d.com/comparing-bowden-vs-direct-drive-3d-printer/
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