http://europepmc.org/abstract/MED/22037554
http://europepmc.org/abstract/MED/30239046
http://europepmc.org/abstract/MED/25778705
http://europepmc.org/abstract/MED/24011952
http://europepmc.org/abstract/MED/25656989
http://europepmc.org/abstract/MED/26489445