http://europepmc.org/abstract/MED/23632888
http://europepmc.org/abstract/MED/23889083
http://europepmc.org/abstract/MED/24218139
http://europepmc.org/abstract/MED/19388938
http://europepmc.org/abstract/MED/23319568
http://europepmc.org/abstract/MED/24077845
http://europepmc.org/abstract/MED/24697267
http://europepmc.org/abstract/MED/25809997
http://europepmc.org/abstract/MED/27486981
http://europepmc.org/abstract/MED/27029036
http://europepmc.org/abstract/MED/24045501
http://europepmc.org/abstract/MED/21828135
http://europepmc.org/abstract/MED/23531518
http://europepmc.org/abstract/MED/21339759
http://europepmc.org/abstract/MED/24030381
http://europepmc.org/abstract/MED/26648538
http://europepmc.org/abstract/MED/22912701
http://europepmc.org/abstract/MED/21909114
http://europepmc.org/abstract/MED/23774674