"Atmung" (https://kmed.uni-giessen.de/ilias/goto.php?target=pg_44999_167119) . The file “Ausdehnung der Lunge bei Ein- (blau) und Ausatmung (rosa)” from Wikipedia (https://de.wikipedia.org/wiki/Lunge#/media/Datei:Thoracic_landmarks_anterior_view.svg) is licensed under the Creative Commons Attribution 2.5 License 2006 Unported license. The file was adapted (language and descprtion lines chanced) by Prof. Vorwerk (https://www.youtube.com/channel/UCpBHT7vSwpHdOQdVJ2IYdGA) can be reused under the the same conditions like the original file.