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YoungHelm. Spektrale Lichtempfindlichkeiten der Zapfen im menschlichem Auge Hermann von Helmholtz Gesammelte Schriften III OlmsWeidmann Fig by Hermann von Helmhotz PDold Original upload log page de YoungHelm Analemma bytes no Information spektrale Lichtempfindlichkeiten der Zapfen im menschlischem Auge Hermann von Helmhotz