http://europepmc.org/abstract/MED/12001123
http://europepmc.org/abstract/MED/1348931
http://europepmc.org/abstract/MED/15161705
http://europepmc.org/abstract/MED/26317919
http://europepmc.org/abstract/MED/7549812
http://europepmc.org/abstract/MED/27105513
http://europepmc.org/abstract/MED/10091733
http://europepmc.org/abstract/MED/23856246
http://europepmc.org/abstract/MED/9683299
http://europepmc.org/abstract/MED/8664051
http://europepmc.org/abstract/MED/24942490
http://europepmc.org/abstract/MED/7767998
http://europepmc.org/abstract/MED/17473653
http://europepmc.org/abstract/MED/26599269
http://europepmc.org/abstract/MED/9846966
http://europepmc.org/abstract/MED/1347094
http://europepmc.org/abstract/MED/17001163
http://europepmc.org/abstract/MED/22696596
http://europepmc.org/abstract/MED/9218731
http://europepmc.org/abstract/MED/1324794
http://europepmc.org/abstract/MED/29681454
http://europepmc.org/abstract/MED/8794405
http://europepmc.org/abstract/MED/7615358
http://europepmc.org/abstract/MED/10830574
http://europepmc.org/abstract/MED/15564288