http://europepmc.org/abstract/MED/25957691
http://europepmc.org/abstract/MED/23856246
http://europepmc.org/abstract/MED/29844865
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/28978093
http://europepmc.org/abstract/MED/25617745
http://europepmc.org/abstract/MED/16959974
http://europepmc.org/abstract/MED/8752209
http://europepmc.org/abstract/MED/22895193
http://europepmc.org/abstract/MED/25344691