http://europepmc.org/abstract/MED/12394763
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/24121792
http://europepmc.org/abstract/MED/11585741
http://europepmc.org/abstract/MED/21533174
http://europepmc.org/abstract/MED/28945843