http://europepmc.org/abstract/MED/25652455
http://europepmc.org/abstract/MED/27288520
http://europepmc.org/abstract/MED/27063598
http://europepmc.org/abstract/MED/27276561
http://europepmc.org/abstract/MED/24056718
http://europepmc.org/abstract/MED/25412851