http://www.news.wisc.edu/8413
http://truth4pets.org/2012/06/what-everyone-needs-to-know/
http://www.dogs4dogs.com/blog/2011/11/15/new-canine-vaccination-guidelines/
http://drjeandoddspethealthresource.tumblr.com/post/51665176980/leptospirosis-dog-vaccines#.Uj8jy4a9nJY
http://drjeandoddspethealthresource.tumblr.com/post/33789611348/changing-pet-vaccine-protocol#.Uj8oFIa9nJY