http://europepmc.org/abstract/MED/27284958
http://europepmc.org/abstract/MED/23856246
http://europepmc.org/abstract/MED/27925203
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/29420467
http://europepmc.org/abstract/MED/27135926
http://europepmc.org/abstract/MED/25961742
http://europepmc.org/abstract/MED/28921573