http://onlinelibrary.wiley.com/doi/10.1046/j.1365-294x.2000.01030.x/full
http://onlinelibrary.wiley.com/doi/10.1111/j.1556-4029.2008.00857.x/full
http://informahealthcare.com/doi/abs/10.3109/19401736.2010.491864
http://jhered.oxfordjournals.org/content/100/3/297.short
http://europepmc.org/abstract/cba/292259
http://jhered.oxfordjournals.org/content/102/2/165.short