http://europepmc.org/abstract/MED/25957691
http://europepmc.org/abstract/MED/10737795
http://europepmc.org/abstract/MED/28465371
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/11920497
http://europepmc.org/abstract/MED/22810696
http://europepmc.org/abstract/MED/12524418
http://europepmc.org/abstract/MED/26071483
http://europepmc.org/abstract/MED/20951698
http://europepmc.org/abstract/MED/28978093
http://europepmc.org/abstract/MED/27004155
http://europepmc.org/abstract/MED/7927902
http://europepmc.org/abstract/MED/20544848
http://europepmc.org/abstract/MED/12408524
http://europepmc.org/abstract/MED/23354438
http://europepmc.org/abstract/MED/12110635
http://europepmc.org/abstract/MED/25344691
http://europepmc.org/abstract/MED/26109429
http://europepmc.org/abstract/MED/9482574