http://europepmc.org/abstract/MED/24816253
http://europepmc.org/abstract/MED/8129036
http://europepmc.org/abstract/MED/10748875
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/11895856
http://europepmc.org/abstract/MED/30239046
http://europepmc.org/abstract/MED/11837710