http://europepmc.org/abstract/MED/27149842
http://europepmc.org/abstract/MED/24755471
http://europepmc.org/abstract/MED/30200630
http://europepmc.org/abstract/MED/28577310
http://europepmc.org/abstract/MED/27302833
http://europepmc.org/abstract/MED/23700467
http://europepmc.org/abstract/MED/26648449
http://europepmc.org/abstract/MED/28002797