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Keywords from Image Description:
Refraktion. Traveltime curves of the direct blue and critically refracted green wave Knickpunkt is the german word for crossover point Laufzeitkurven der direkten und der refraktrierten Welle mit Strahlwegen unten und einigen Fachbegriffen own work created with Xfig April April Ingo Wlbern the creator of this figure provide