http://ocp.hul.harvard.edu/contagion/koch.html http://ocp.hul.harvard.edu/contagion/koch.html Contagion: Historical views of diseases and epidemics http://ocp.hul.harvard.edu/contagion/koch.html http://ocp.hul.harvard.edu/contagion/koch.html http://ocp.hul.harvard.edu/contagion/koch.html http://ocp.hul.harvard.edu/contagion/koch.html http://ocp.hul.harvard.edu/contagion/koch.html Robert Koch http://ocp.hul.harvard.edu/contagion/koch.html http://ocp.hul.harvard.edu/contagion/koch.html Robert Koch http://ocp.hul.harvard.edu/contagion/koch.html Robert Koch http://ocp.hul.harvard.edu/contagion/koch.html Robert Koch http://ocp.hul.harvard.edu/contagion/koch.html