http://europepmc.org/abstract/MED/16680592
http://europepmc.org/abstract/MED/11293895
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/23349472
http://europepmc.org/abstract/MED/10363573
http://europepmc.org/abstract/MED/18024325
http://europepmc.org/abstract/MED/11106555