http://veg-fruit.cropsci.uiuc.edu/new/apples18.asp
http://www.aces.uiuc.edu/vista/abstracts/a801.html
http://www.caf.wvu.edu/kearneysville/disease_descriptions
/omblight.html
Biology and Epidemiology of Fire Blight
http://www.caf.wvu.edu/kearneysville/disease_descriptions
/omapscab.html
http://veg-fruit.cropsci.uiuc.edu/new/News2004.asp